Merge commit '107ce3050fc37b9a13d8304ae1bb73fac9de5f61'

52 files changed, 619 insertions, 313 deletions

diff --git a/lisp/calc/calc-prog.el b/lisp/calc/calc-prog.el
index ba8efd43b8e..37e10e8dfac 100644
--- a/lisp/calc/calc-prog.el
+++ b/lisp/calc/calc-prog.el
@@ -1097,7 +1097,7 @@ Redefine the corresponding command."
        (or func (setq func (and cmd (symbolp cmd) (fboundp cmd) cmd)))
        (if (get func 'math-compose-forms)
            (let ((pt (point)))
-             (insert "(put '" (symbol-name cmd)
+             (insert "(put '" (symbol-name func)
                      " 'math-compose-forms '"
                      (prin1-to-string (get func 'math-compose-forms))
                      ")\n")
diff --git a/lisp/cus-edit.el b/lisp/cus-edit.el
index 8a8bad91137..24969633373 100644
--- a/lisp/cus-edit.el
+++ b/lisp/cus-edit.el
@@ -2212,7 +2212,12 @@ and `face'."
     (unless (eq state 'modified)
       (unless (memq state '(nil unknown hidden))
         (widget-put widget :custom-state 'modified))
-      (custom-magic-reset widget)
+      ;; Update the status text (usually from "STANDARD" to "EDITED
+      ;; bla bla" in the buffer after the command has run.  Otherwise
+      ;; commands like `M-u' (that work on a region in the buffer)
+      ;; will upcase the wrong part of the buffer, since more text has
+      ;; been inserted before point.
+      (run-with-idle-timer 0.0 nil #'custom-magic-reset widget)
       (apply 'widget-default-notify widget args))))
 
 (defun custom-redraw (widget)
diff --git a/lisp/emacs-lisp/autoload.el b/lisp/emacs-lisp/autoload.el
index a2dbd402c52..ce2827162b9 100644
--- a/lisp/emacs-lisp/autoload.el
+++ b/lisp/emacs-lisp/autoload.el
@@ -398,9 +398,8 @@ FILE's name."
   ;; Probably pointless, but replaces the old AUTOGEN_VCS in lisp/Makefile,
   ;; which was designed to handle CVSREAD=1 and equivalent.
   (and autoload-ensure-writable
-       (file-exists-p file)
        (let ((modes (file-modes file)))
-         (if (zerop (logand modes #o0200))
+         (if (and modes (zerop (logand modes #o0200)))
              ;; Ignore any errors here, and let subsequent attempts
              ;; to write the file raise any real error.
              (ignore-errors (set-file-modes file (logior modes #o0200))))))
diff --git a/lisp/emacs-lisp/backtrace.el b/lisp/emacs-lisp/backtrace.el
index 60d146e24a8..0c4c7987c3c 100644
--- a/lisp/emacs-lisp/backtrace.el
+++ b/lisp/emacs-lisp/backtrace.el
@@ -175,7 +175,8 @@ This should be a list of `backtrace-frame' objects.")
 
 (defvar-local backtrace-view nil
   "A plist describing how to render backtrace frames.
-Possible entries are :show-flags, :show-locals and :print-circle.")
+Possible entries are :show-flags, :show-locals, :print-circle
+and :print-gensym.")
 
 (defvar-local backtrace-insert-header-function nil
   "Function for inserting a header for the current Backtrace buffer.
@@ -205,6 +206,7 @@ frames where the source code location is known.")
     (define-key map "p" 'backtrace-backward-frame)
     (define-key map "v" 'backtrace-toggle-locals)
     (define-key map "#" 'backtrace-toggle-print-circle)
+    (define-key map ":" 'backtrace-toggle-print-gensym)
     (define-key map "s" 'backtrace-goto-source)
     (define-key map "\C-m" 'backtrace-help-follow-symbol)
     (define-key map "+" 'backtrace-multi-line)
@@ -224,6 +226,18 @@ frames where the source code location is known.")
          :active (backtrace-get-index)
          :selected (plist-get (backtrace-get-view) :show-locals)
          :help "Show or hide the local variables for the frame at point"]
+        ["Show Circular Structures" backtrace-toggle-print-circle
+         :style toggle
+         :active (backtrace-get-index)
+         :selected (plist-get (backtrace-get-view) :print-circle)
+         :help
+         "Condense or expand shared or circular structures in the frame at point"]
+        ["Show Uninterned Symbols" backtrace-toggle-print-gensym
+         :style toggle
+         :active (backtrace-get-index)
+         :selected (plist-get (backtrace-get-view) :print-gensym)
+         :help
+         "Toggle unique printing of uninterned symbols in the frame at point"]
         ["Expand \"...\"s" backtrace-expand-ellipses
          :help "Expand all the abbreviated forms in the current frame"]
         ["Show on Multiple Lines" backtrace-multi-line
@@ -339,6 +353,7 @@ It runs `backtrace-revert-hook', then calls `backtrace-print'."
   `(let ((print-escape-control-characters t)
          (print-escape-newlines t)
          (print-circle (plist-get ,view :print-circle))
+         (print-gensym (plist-get ,view :print-gensym))
          (standard-output (current-buffer)))
      ,@body))
 
@@ -420,12 +435,18 @@ Set it to VALUE unless the button is a `backtrace-ellipsis' button."
 
 (defun backtrace-toggle-print-circle (&optional all)
   "Toggle `print-circle' for the backtrace frame at point.
-With prefix argument ALL, toggle the value of :print-circle in
-`backtrace-view', which affects all of the backtrace frames in
-the buffer."
+With prefix argument ALL, toggle the default value bound to
+`print-circle' for all the frames in the buffer."
   (interactive "P")
   (backtrace--toggle-feature :print-circle all))
 
+(defun backtrace-toggle-print-gensym (&optional all)
+  "Toggle `print-gensym' for the backtrace frame at point.
+With prefix argument ALL, toggle the default value bound to
+`print-gensym' for all the frames in the buffer."
+  (interactive "P")
+  (backtrace--toggle-feature :print-gensym all))
+
 (defun backtrace--toggle-feature (feature all)
   "Toggle FEATURE for the current backtrace frame or for the buffer.
 FEATURE should be one of the options in `backtrace-view'.  If ALL
@@ -450,12 +471,15 @@ position point at the start of the frame it was in before."
           (goto-char (point-min))
           (while (and (not (eql index (backtrace-get-index)))
                       (< (point) (point-max)))
-            (goto-char (backtrace-get-frame-end)))))
-    (let ((index (backtrace-get-index)))
-      (unless index
-        (user-error "Not in a stack frame"))
-      (backtrace--set-feature feature
-                              (not (plist-get (backtrace-get-view) feature))))))
+            (goto-char (backtrace-get-frame-end))))
+        (message "%s is now %s for all frames"
+                 (substring (symbol-name feature) 1) value))
+    (unless (backtrace-get-index)
+      (user-error "Not in a stack frame"))
+    (let ((value (not (plist-get (backtrace-get-view) feature))))
+      (backtrace--set-feature feature value)
+      (message "%s is now %s for this frame"
+               (substring (symbol-name feature) 1) value))))
 
 (defun backtrace--set-feature (feature value)
   "Set FEATURE in the view plist of the frame at point to VALUE.
diff --git a/lisp/emacs-lisp/cl-print.el b/lisp/emacs-lisp/cl-print.el
index 5fe3dd1b912..530770128e6 100644
--- a/lisp/emacs-lisp/cl-print.el
+++ b/lisp/emacs-lisp/cl-print.el
@@ -548,21 +548,22 @@ limit."
   ;; call_debugger (bug#31919).
   (let* ((print-length (when limit (min limit 50)))
          (print-level (when limit (min 8 (truncate (log limit)))))
-         (delta (when limit
-                  (max 1 (truncate (/ print-length print-level))))))
+         (delta-length (when limit
+                         (max 1 (truncate (/ print-length print-level))))))
     (with-temp-buffer
       (catch 'done
         (while t
           (erase-buffer)
           (funcall print-function value (current-buffer))
-          ;; Stop when either print-level is too low or the value is
-          ;; successfully printed in the space allowed.
-          (when (or (not limit)
-                    (< (- (point-max) (point-min)) limit)
-                    (= print-level 2))
-            (throw 'done (buffer-string)))
-          (cl-decf print-level)
-          (cl-decf print-length delta))))))
+          (let ((result (- (point-max) (point-min))))
+            ;; Stop when either print-level is too low or the value is
+            ;; successfully printed in the space allowed.
+            (when (or (not limit) (< result limit) (<= print-level 2))
+              (throw 'done (buffer-string)))
+            (let* ((ratio (/ result limit))
+                   (delta-level (max 1 (min (- print-level 2) ratio))))
+              (cl-decf print-level delta-level)
+              (cl-decf print-length (* delta-length delta-level)))))))))
 
 (provide 'cl-print)
 ;;; cl-print.el ends here
diff --git a/lisp/emacs-lisp/elint.el b/lisp/emacs-lisp/elint.el
index b7ef6eeb2ae..187d619f1bc 100644
--- a/lisp/emacs-lisp/elint.el
+++ b/lisp/emacs-lisp/elint.el
@@ -106,7 +106,7 @@ are as follows, and suppress messages about the indicated features:
   :group 'elint)
 
 (defcustom elint-directory-skip-re "\\(ldefs-boot\\|loaddefs\\)\\.el\\'"
-  "If nil, a regexp matching files to skip when linting a directory."
+  "If non-nil, a regexp matching files to skip when linting a directory."
   :type '(choice (const :tag "Lint all files" nil)
                  (regexp :tag "Regexp to skip"))
   :safe 'string-or-null-p
diff --git a/lisp/emulation/viper.el b/lisp/emulation/viper.el
index 521edbe6048..0f5c92c2c9e 100644
--- a/lisp/emulation/viper.el
+++ b/lisp/emulation/viper.el
@@ -1,4 +1,4 @@
-;;; viper.el --- A full-featured Vi emulator for Emacs and XEmacs,  -*-lexical-binding:t -*-
+;;; viper.el --- A full-featured Vi emulator for Emacs  -*- lexical-binding:t -*-
 ;;               a VI Plan for Emacs Rescue,
 ;;               and a venomous VI PERil.
 ;;               Viper Is also a Package for Emacs Rebels.
@@ -34,7 +34,7 @@
 
 ;;; Commentary:
 
-;; Viper is a full-featured Vi emulator for Emacs and XEmacs.  It emulates and
+;; Viper is a full-featured Vi emulator for Emacs.  It emulates and
 ;; improves upon the standard features of Vi and, at the same time, allows
 ;; full access to all Emacs facilities.  Viper supports multiple undo,
 ;; file name completion, command, file, and search history and it extends
@@ -541,7 +541,7 @@ If Viper is enabled, turn it off.  Otherwise, turn it on."
                       "Viper Is a Package for Emacs Rebels,
 a VI Plan for Emacs Rescue, and a venomous VI PERil.
 
-Incidentally, Viper emulates Vi under Emacs/XEmacs 20.
+Incidentally, Viper emulates Vi under Emacs.
 It supports all of what is good in Vi and Ex, while extending
 and improving upon much of it.
 
diff --git a/lisp/files.el b/lisp/files.el
index ce4dd99bd53..5ceaacd744e 100644
--- a/lisp/files.el
+++ b/lisp/files.el
@@ -2554,13 +2554,13 @@ unless NOMODES is non-nil."
       (auto-save-mode 1)))
   ;; Make people do a little extra work (C-x C-q)
   ;; before altering a backup file.
-  (when (backup-file-name-p buffer-file-name)
-    (setq buffer-read-only t))
   ;; When a file is marked read-only,
   ;; make the buffer read-only even if root is looking at it.
-  (when (and (file-modes (buffer-file-name))
-             (zerop (logand (file-modes (buffer-file-name)) #o222)))
-    (setq buffer-read-only t))
+  (unless buffer-read-only
+    (when (or (backup-file-name-p buffer-file-name)
+              (let ((modes (file-modes (buffer-file-name))))
+                (and modes (zerop (logand modes #o222)))))
+      (setq buffer-read-only t)))
   (unless nomodes
     (when (and view-read-only view-mode)
       (view-mode -1))
diff --git a/lisp/gnus/gnus-art.el b/lisp/gnus/gnus-art.el
index 04cb087737f..eba66c1c3aa 100644
--- a/lisp/gnus/gnus-art.el
+++ b/lisp/gnus/gnus-art.el
@@ -5378,9 +5378,9 @@ Compressed files like .gz and .bz2 are decompressed."
                                     'gnus-undeletable t))))
           ;; We're in the article header.
           (delete-char -1)
-          (dolist (ovl (overlays-in btn (point)))
+          (let ((ovl (make-overlay btn (point))))
             (overlay-put ovl 'gnus-button-attachment-extra t)
-            (overlay-put ovl 'face nil))
+            (overlay-put ovl 'evaporate t))
           (save-restriction
             (message-narrow-to-field)
             (let ((gnus-treatment-function-alist
@@ -5763,9 +5763,9 @@ all parts."
                                     'gnus-undeletable t))))
           ;; We're in the article header.
           (delete-char -1)
-          (dolist (ovl (overlays-in point (point)))
+          (let ((ovl (make-overlay point (point))))
             (overlay-put ovl 'gnus-button-attachment-extra t)
-            (overlay-put ovl 'face nil))
+            (overlay-put ovl 'evaporate t))
           (save-restriction
             (message-narrow-to-field)
             (let ((gnus-treatment-function-alist
@@ -6379,9 +6379,9 @@ in the body.  Use `gnus-header-face-alist' to highlight buttons."
                   (insert "\n")
                   (end-of-line)))
               (insert "\n")
-              (dolist (ovl (overlays-in (point-min) (point)))
+              (let ((ovl (make-overlay (point-min) (point))))
                 (overlay-put ovl 'gnus-button-attachment-extra t)
-                (overlay-put ovl 'face nil))
+                (overlay-put ovl 'evaporate t))
               (let ((gnus-treatment-function-alist
                      '((gnus-treat-highlight-headers
                         gnus-article-highlight-headers))))
diff --git a/lisp/gnus/gnus-start.el b/lisp/gnus/gnus-start.el
index e8775c66673..cb369f07b92 100644
--- a/lisp/gnus/gnus-start.el
+++ b/lisp/gnus/gnus-start.el
@@ -897,9 +897,8 @@ If REGEXP is given, lines that match it will be deleted."
             (set-buffer-modified-p t))
           ;; Set the file modes to reflect the .newsrc file modes.
           (save-buffer)
-          (when (and (file-exists-p gnus-current-startup-file)
-                     (file-exists-p dribble-file)
-                     (setq modes (file-modes gnus-current-startup-file)))
+          (when (and (setq modes (file-modes gnus-current-startup-file))
+                     (file-exists-p dribble-file))
             (gnus-set-file-modes dribble-file modes))
           (goto-char (point-min))
           (when (search-forward "Gnus was exited on purpose" nil t)
diff --git a/lisp/gnus/mm-decode.el b/lisp/gnus/mm-decode.el
index cba9633b539..5636b8eca47 100644
--- a/lisp/gnus/mm-decode.el
+++ b/lisp/gnus/mm-decode.el
@@ -381,9 +381,11 @@ enables you to choose manually one of two types those mails include."
   :type 'directory
   :group 'mime-display)
 
-(defcustom mm-inline-large-images nil
-  "If t, then all images fit in the buffer.
-If `resize', try to resize the images so they fit."
+(defcustom mm-inline-large-images 'resize
+  "If nil, images larger than the window aren't displayed in the buffer.
+If `resize', try to resize the images so they fit in the buffer.
+If t, show the images as they are without resizing."
+  :version "27.1"
   :type '(radio
           (const :tag "Inline large images as they are." t)
           (const :tag "Resize large images." resize)
diff --git a/lisp/gnus/mm-view.el b/lisp/gnus/mm-view.el
index 6ffa1fc168d..02d99200a35 100644
--- a/lisp/gnus/mm-view.el
+++ b/lisp/gnus/mm-view.el
@@ -65,8 +65,9 @@
   :group 'mime-display)
 
 (defcustom mm-inline-large-images-proportion 0.9
-  "Maximum proportion of large image resized when
-`mm-inline-large-images' is set to resize."
+  "Maximum proportion large images can occupy in the buffer.
+This is only used if `mm-inline-large-images' is set to
+`resize'."
   :type 'float
   :version "24.1"
   :group 'mime-display)
diff --git a/lisp/help-mode.el b/lisp/help-mode.el
index fb29bd2be4f..efc0b8ffa9e 100644
--- a/lisp/help-mode.el
+++ b/lisp/help-mode.el
@@ -59,7 +59,7 @@
     ["Next Topic" help-go-forward
      :help "Go back to next topic in this help buffer"]
     ["Move to Previous Button" backward-button
-     :help "Move to the Next Button in the help buffer"]
+     :help "Move to the Previous Button in the help buffer"]
     ["Move to Next Button" forward-button
       :help "Move to the Next Button in the help buffer"]))
 
diff --git a/lisp/htmlfontify.el b/lisp/htmlfontify.el
index b8442be1e89..c1aaab5e211 100644
--- a/lisp/htmlfontify.el
+++ b/lisp/htmlfontify.el
@@ -1938,9 +1938,9 @@ adding an extension of `hfy-extn'.  Fontification is actually done by
                  (set-buffer  html)
                  (write-file (concat target hfy-extn))
                  (kill-buffer html))
-        ;; #o0200 == 128, but emacs20 doesn't know that
-        (if (and (file-exists-p target) (not (file-writable-p target)))
-            (set-file-modes target (logior (file-modes target) 128)))
+        (let ((modes (file-modes target)))
+          (if (and modes (not (file-writable-p target)))
+              (set-file-modes target (logior modes #o0200))))
         (copy-file (buffer-file-name source) target 'overwrite))
       (kill-buffer source)) ))
 
diff --git a/lisp/imenu.el b/lisp/imenu.el
index 5084fe61eff..9df597b4d63 100644
--- a/lisp/imenu.el
+++ b/lisp/imenu.el
@@ -510,8 +510,9 @@ See `imenu--index-alist' for the format of the index alist."
        "No items suitable for an index found in this buffer"))
   (or imenu--index-alist
       (setq imenu--index-alist (list nil)))
-  ;; Add a rescan option to the index.
-  (cons imenu--rescan-item imenu--index-alist))
+  (unless imenu-auto-rescan
+    ;; Add a rescan option to the index.
+    (cons imenu--rescan-item imenu--index-alist)))
 
 (defvar imenu--cleanup-seen nil)
 
diff --git a/lisp/international/fontset.el b/lisp/international/fontset.el
index f3ab81633dc..1debec7f469 100644
--- a/lisp/international/fontset.el
+++ b/lisp/international/fontset.el
@@ -719,6 +719,7 @@
                     symbol
                     braille
                     yi
+                    tai-viet
                     aegean-number
                     ancient-greek-number
                     ancient-symbol
@@ -731,18 +732,26 @@
                     deseret
                     shavian
                     osmanya
+                    osage
                     cypriot-syllabary
                     phoenician
                     lydian
                     kharoshthi
+                    manichaean
+                    elymaic
+                    makasar
                     cuneiform-numbers-and-punctuation
                     cuneiform
                     egyptian
+                    bassa-vah
+                    pahawh-hmong
+                    medefaidrin
                     byzantine-musical-symbol
                     musical-symbol
                     ancient-greek-musical-notation
                     tai-xuan-jing-symbol
                     counting-rod-numeral
+                    adlam
                     mahjong-tile
                     domino-tile))
     (set-fontset-font "fontset-default"
diff --git a/lisp/international/iso-transl.el b/lisp/international/iso-transl.el
index b573e1e47c5..3530e6f2538 100644
--- a/lisp/international/iso-transl.el
+++ b/lisp/international/iso-transl.el
@@ -177,6 +177,8 @@
     ("c"    . [?¢])
     ("*o"   . [?°])
     ("o"    . [?°])
+    ("Oe"   . [?œ])
+    ("OE"   . [?Œ])
     ("*u"   . [?µ])
     ("u"    . [?µ])
     ("*m"   . [?µ])
diff --git a/lisp/isearch.el b/lisp/isearch.el
index 30f7fc7254c..ec51c2cf4cc 100644
--- a/lisp/isearch.el
+++ b/lisp/isearch.el
@@ -514,6 +514,9 @@ This is like `describe-bindings', but displays only Isearch keys."
     (define-key map [isearch-yank-kill]
       '(menu-item "Current kill" isearch-yank-kill
                   :help "Append current kill to search string"))
+    (define-key map [isearch-yank-until-char]
+      '(menu-item "Until char..." isearch-yank-until-char
+                  :help "Yank from point to specified character into search string"))
     (define-key map [isearch-yank-line]
       '(menu-item "Rest of line" isearch-yank-line
                   :help "Yank the rest of the current line on search string"))
@@ -705,6 +708,7 @@ This is like `describe-bindings', but displays only Isearch keys."
     (define-key map "\M-\C-d" 'isearch-del-char)
     (define-key map "\M-\C-y" 'isearch-yank-char)
     (define-key map    "\C-y" 'isearch-yank-kill)
+    (define-key map "\M-\C-z" 'isearch-yank-until-char)
     (define-key map "\M-s\C-e" 'isearch-yank-line)
 
     (define-key map "\M-s\M-<" 'isearch-beginning-of-buffer)
@@ -998,6 +1002,8 @@ Type \\[isearch-yank-word-or-char] to yank next word or character in buffer
 Type \\[isearch-del-char] to delete character from end of search string.
 Type \\[isearch-yank-char] to yank char from buffer onto end of search\
  string and search for it.
+Type \\[isearch-yank-until-char] to yank from point until the next instance of a
+ specified character onto end of search string and search for it.
 Type \\[isearch-yank-line] to yank rest of line onto end of search string\
  and search for it.
 Type \\[isearch-yank-kill] to yank the last string of killed text.
@@ -1364,7 +1370,6 @@ NOPUSH is t and EDIT is t."
   (remove-hook 'post-command-hook 'isearch-post-command-hook)
   (remove-hook 'mouse-leave-buffer-hook 'isearch-mouse-leave-buffer)
   (remove-hook 'kbd-macro-termination-hook 'isearch-done)
-  (setq isearch-lazy-highlight-start nil)
   (when (buffer-live-p isearch--current-buffer)
     (with-current-buffer isearch--current-buffer
       (setq isearch--current-buffer nil)
@@ -2562,6 +2567,23 @@ If optional ARG is non-nil, pull in the next ARG words."
   (interactive "p")
   (isearch-yank-internal (lambda () (forward-word arg) (point))))
 
+(defun isearch-yank-until-char (char)
+  "Pull everything until next instance of CHAR from buffer into search string.
+Interactively, prompt for CHAR.
+This is often useful for keyboard macros, for example in programming
+languages or markup languages in which CHAR marks a token boundary."
+  (interactive "cYank until character: ")
+  (isearch-yank-internal
+   (lambda () (let ((inhibit-field-text-motion t))
+                (condition-case nil
+                    (progn
+                      (search-forward (char-to-string char))
+                      (forward-char -1))
+                  (search-failed
+                   (message "`%c' not found" char)
+                   (sit-for 2)))
+                (point)))))
+
 (defun isearch-yank-line (&optional arg)
   "Pull rest of line from buffer into search string.
 If optional ARG is non-nil, yank the next ARG lines."
@@ -3947,8 +3969,9 @@ Attempt to do the search exactly the way the pending Isearch would."
                   (if isearch-lazy-highlight-forward
                       (setq isearch-lazy-highlight-end (point-min))
                     (setq isearch-lazy-highlight-start (point-max)))
-                  (run-at-time lazy-highlight-interval nil
-                               'isearch-lazy-highlight-buffer-update))
+                  (setq isearch-lazy-highlight-timer
+                        (run-at-time lazy-highlight-interval nil
+                                     'isearch-lazy-highlight-buffer-update)))
               (setq isearch-lazy-highlight-timer
                     (run-at-time lazy-highlight-interval nil
                                  'isearch-lazy-highlight-update)))))))))
diff --git a/lisp/language/tai-viet.el b/lisp/language/tai-viet.el
index b202abf029c..086483da813 100644
--- a/lisp/language/tai-viet.el
+++ b/lisp/language/tai-viet.el
@@ -39,21 +39,20 @@
               (input-method . "tai-sonla")
               (sample-text . "TaiViet (ꪁꪫꪱꪣ ꪼꪕ)\t\tꪅꪰꪙꫂ ꪨꪮꫂ ꪁꪫꪱ / ꪅꪽ ꪨꪷ ꪁꪫꪱ")
               (documentation . "\
-TaiViet refers to the Tai language used by Tai people in
-Vietnam, and also refers to the script used for this language.
-Both the script and language have the same origin as that of Thai
+TaiViet refers to the Tai script, which is used to write several
+Tai languages of northwestern Vietnam and surrounding areas.  These
+languages are Tai Dam (also known as Black Tai or Tai Noir),
+Tai Dón (also known as White Tai or Tai Blanc), Tày Tac,
+Tai Daeng (also known as Red Tai or Tai Rouge),
+and Thai Song (also known as Lao Song).  However, some people
+consider Tai Dam, Tai Dón and Tai Daeng to be dialects of the
+same language, and call them collectively \"Tai Viet\".
+
+Both the script and languages have the same origin as that of Thai
 language/script used in Thailand, but now they differ from each
 other in a significant way (especially the scripts are).
 
 The language name is spelled as \"ꪁꪫꪱꪣ ꪼꪕ\", and the script name is
-spelled as \"ꪎ ꪼꪕ\" in the modern form, \"ꪎꪳ ꪼꪕ\" in the traditional
-form.
-
-As the proposal for TaiViet script to the Unicode is still on
-the progress, we use the Private Use Area for TaiViet
-characters (U+F000..U+F07E).  A TaiViet font encoded accordingly
-is available at this web page:
-    http://www.m17n.org/viettai/
-")))
+spelled as \"ꪎꪳ ꪼꪕ\".")))
 
 (provide 'tai-viet)
diff --git a/lisp/leim/quail/ipa-praat.el b/lisp/leim/quail/ipa-praat.el
index 74a2dccc060..169dbcf0e22 100644
--- a/lisp/leim/quail/ipa-praat.el
+++ b/lisp/leim/quail/ipa-praat.el
@@ -148,7 +148,14 @@ input | example | description
 \\'1   | ˈ       | primary stress
 \\'2   | ˌ       | secondary stress
 \\cn   | t̚       | unreleased plosive
-\\rh   | ɜ˞      | rhotacized vowel
+\\hr   | ɜ˞      | rhotacized vowel
+\\^h   | ʰ       | aspiration
+\\^H   | ʱ       | voiced aspiration
+\\^w   | ʷ       | labialized, rounded
+\\^j   | ʲ       | palatalized
+\\^g   | ˠ       | velarized
+\\^9   | ˤ       | pharyngealized
+
 
 - Understrikes
 
@@ -168,7 +175,7 @@ input | example | description
 \\Uv   | d̺       | apical
 \\Dv   | d̻       | laminal
 \\nv   | u̯       | nonsyllabic
-\\e3v  | e̹       | slightly rounded
+\\3v   | e̹       | slightly rounded
 \\cv   | u̜       | slightly unrounded
 
 - Overstrikes
@@ -176,14 +183,14 @@ input | example | description
 input | example | description
 ------+---------+--------------------------------------------
 \\0^   | ɣ̊       | voiceless
-\\'^   |         | high tone
-\\`^   |         | low tone
-\\-^   |         | mid tone
-\\~^   |         | nasalized
-\\v^   |         | rising tone
-\\^^   |         | falling tone
-\\:^   |         | centralized
-\\N^   |         | short
+\\'^   | é       | high tone
+\\`^   | è       | low tone
+\\-^   | ē       | mid tone
+\\~^   | ẽ       | nasalized
+\\v^   | ě       | rising tone
+\\^^   | ê       | falling tone
+\\:^   | ë       | centralized
+\\N^   | ĕ       | short
 \\li   | k͡p      | simultaneous articulation or single segment
 "
  nil t nil nil nil nil nil nil nil nil t)
@@ -308,7 +315,13 @@ input | example | description
  ("\\'1" ?ˈ) ; primary stress
  ("\\'2" ?ˌ) ; secondary stress
  ("\\cn" #x031A) ; t̚ unreleased plosive
- ("\\rh" #x02DE) ; ɜ˞ rhotacized vowel
+ ("\\hr" #x02DE) ; ɜ˞ rhotacized vowel
+ ("\\^h" ?ʰ) ; ʰ aspiration (usually following a plosive)
+ ("\\^H" ?ʱ) ; ʱ voiced aspiration (usually following a plosive)
+ ("\\^w" ?ʷ) ; labialized
+ ("\\^j" ?ʲ) ; palatalized
+ ("\\^g" ?ˠ) ; velarized
+ ("\\^9" ?ˤ) ; pharyngealized
 
  ("\\|v" #x0329) ; n̩ syllabic consonant
  ("\\0v" #x0325) ; b̥ voiceless
@@ -324,7 +337,7 @@ input | example | description
  ("\\Uv" #x033A) ; d̺ apical
  ("\\Dv" #x033B) ; d̻ laminal
  ("\\nv" #x032F) ; u̯ nonsyllabic
- ("\\e3v" #x0339) ; e̹ slightly rounded
+ ("\\3v" #x0339) ; e̹ slightly rounded
  ("\\cv" #x031C) ; u̜ slightly unrounded
 
  ("\\0^" #x030A) ; ɣ̊ voiceless
diff --git a/lisp/mail/feedmail.el b/lisp/mail/feedmail.el
index babc3fc212a..b362614d3a0 100644
--- a/lisp/mail/feedmail.el
+++ b/lisp/mail/feedmail.el
@@ -17,15 +17,6 @@
 ;; ability to queue messages for later sending.  This replaces
 ;; the standalone fakemail program that used to be distributed with Emacs.
 
-;; feedmail works with recent versions of Emacs (20.x series) and
-;; XEmacs (tested with 20.4 and later betas).  It probably no longer
-;; works with Emacs v18, though I haven't tried that in a long
-;; time.  Makoto.Nakagawa@jp.compaq.com reports: "I have a report
-;; that with a help of APEL library, feedmail works fine under emacs
-;; 19.28.  You can get APEL from ftp://ftp.m17n.org/pub/mule/apel/.
-;; you need apel-10.2 or later to make feedmail work under emacs
-;; 19.28."
-
 ;; Sorry, no manual yet in this release.  Look for one with the next
 ;; release.  Or the one after that.  Or maybe later.
 
@@ -437,9 +428,7 @@ shuttled robotically onward."
 (defcustom feedmail-confirm-outgoing-timeout nil
   "If non-nil, a timeout in seconds at the send confirmation prompt.
 If a positive number, it's a timeout before sending.  If a negative
-number, it's a timeout before not sending.  This will not work if your
-version of Emacs doesn't include the function `y-or-n-p-with-timeout'
-\(e.g., some versions of XEmacs)."
+number, it's a timeout before not sending."
   :version "24.1"
   :group 'feedmail-misc
   :type '(choice (const nil) integer)
@@ -2004,9 +1993,7 @@ backup file names and the like)."
              ((feedmail-fqm-p blobby)
               (setq blobby-buffer (generate-new-buffer (concat "FQM " blobby)))
               (setq already-buffer
-                    (if (fboundp 'find-buffer-visiting) ; missing from XEmacs
-                        (find-buffer-visiting maybe-file)
-                      (get-file-buffer maybe-file)))
+                    (find-buffer-visiting maybe-file))
               (if (and already-buffer (buffer-modified-p already-buffer))
                   (save-window-excursion
                     (display-buffer (set-buffer already-buffer))
diff --git a/lisp/mail/smtpmail.el b/lisp/mail/smtpmail.el
index f6fd1cd65eb..802c9ba788d 100644
--- a/lisp/mail/smtpmail.el
+++ b/lisp/mail/smtpmail.el
@@ -165,6 +165,13 @@ attempt."
   :type '(choice regexp (const :tag "None" nil))
   :version "27.1")
 
+(defcustom smtpmail-retries 10
+  "The number of times smtpmail will retry sending when getting transient errors.
+These are errors with a code of 4xx from the SMTP server, which
+mean \"try again\"."
+  :type 'integer
+  :version "27.1")
+
 ;; End of customizable variables.
 
 
@@ -654,10 +661,12 @@ Returns an error if the server cannot be contacted."
               user-mail-address))))
 
 (defun smtpmail-via-smtp (recipient smtpmail-text-buffer
-                                    &optional ask-for-password)
+                                    &optional ask-for-password
+                                    send-attempts)
   (unless smtpmail-smtp-server
     (smtpmail-query-smtp-server))
   (let ((process nil)
+        (send-attempts (or send-attempts 1))
         (host (or smtpmail-smtp-server
                   (error "`smtpmail-smtp-server' not defined")))
         (port smtpmail-smtp-service)
@@ -819,6 +828,23 @@ Returns an error if the server cannot be contacted."
                ((smtpmail-ok-p (setq result (smtpmail-read-response process)))
                 ;; Success.
                 )
+               ((and (numberp (car result))
+                     (<= 400 (car result) 499)
+                     (< send-attempts smtpmail-retries))
+                (message "Got transient error code %s when sending; retrying attempt %d..."
+                         (car result) send-attempts)
+                ;; Retry on getting a transient 4xx code; see
+                ;; https://tools.ietf.org/html/rfc5321#section-4.2.1
+                (ignore-errors
+                  (smtpmail-send-command process "QUIT")
+                  (smtpmail-read-response process))
+                (delete-process process)
+                (sleep-for 1)
+                (setq process nil)
+                (throw 'done
+                       (smtpmail-via-smtp recipient smtpmail-text-buffer
+                                          ask-for-password
+                                          (1+ send-attempts))))
                ((and auth-mechanisms
                      (not ask-for-password)
                      (eq (car result) 530))
diff --git a/lisp/mh-e/mh-acros.el b/lisp/mh-e/mh-acros.el
index c017419df2e..0f15d3eb71b 100644
--- a/lisp/mh-e/mh-acros.el
+++ b/lisp/mh-e/mh-acros.el
@@ -270,10 +270,16 @@ MH-E functions."
   (declare (debug let) (indent 1))
   ;; Works in both lexical and non-lexical mode.
   `(progn
-     ,@(mapcar (lambda (binder)
-                 `(defvar ,(if (consp binder) (car binder) binder)))
-               binders)
-     (let* ,binders ,@body)))
+     (with-suppressed-warnings ((lexical
+                                 ,@(mapcar (lambda (binder)
+                                             (if (consp binder)
+                                                 (car binder)
+                                               binder))
+                                           binders)))
+       ,@(mapcar (lambda (binder)
+                   `(defvar ,(if (consp binder) (car binder) binder)))
+                 binders)
+       (let* ,binders ,@body))))
 
 (provide 'mh-acros)
 
diff --git a/lisp/net/eww.el b/lisp/net/eww.el
index 77e6cec9b04..fb495a98582 100644
--- a/lisp/net/eww.el
+++ b/lisp/net/eww.el
@@ -326,6 +326,18 @@ the default EWW buffer."
                               #'url-hexify-string (split-string url) "+"))))))
   url)
 
+(defun eww--preprocess-html (start end)
+  "Translate all < characters that do not look like start of tags into &lt;."
+  (save-excursion
+    (save-restriction
+      (narrow-to-region start end)
+      (goto-char start)
+      (let ((case-fold-search t))
+        (while (re-search-forward "<[^0-9a-z!/]" nil t)
+          (goto-char (match-beginning 0))
+          (delete-region (point) (1+ (point)))
+          (insert "&lt;"))))))
+
 ;;;###autoload (defalias 'browse-web 'eww)
 
 ;;;###autoload
@@ -479,6 +491,7 @@ Currently this means either text/html or application/xhtml+xml."
                   ;; Remove CRLF and replace NUL with &#0; before parsing.
                   (while (re-search-forward "\\(\r$\\)\\|\0" nil t)
                     (replace-match (if (match-beginning 1) "" "&#0;") t t)))
+                (eww--preprocess-html (point) (point-max))
                 (libxml-parse-html-region (point) (point-max))))))
         (source (and (null document)
                      (buffer-substring (point) (point-max)))))
@@ -716,6 +729,7 @@ the like."
                 (condition-case nil
                     (decode-coding-region (point-min) (point-max) 'utf-8)
                   (coding-system-error nil))
+                (eww--preprocess-html (point-min) (point-max))
                 (libxml-parse-html-region (point-min) (point-max))))
          (base (plist-get eww-data :url)))
     (eww-score-readability dom)
@@ -1433,15 +1447,15 @@ See URL `https://developer.mozilla.org/en-US/docs/Web/HTML/Element/Input'.")
               (push (cons name (plist-get input :value))
                     values)))
            ((equal (plist-get input :type) "file")
-            (push (cons "file"
-                        (list (cons "filedata"
-                                    (with-temp-buffer
-                                      (insert-file-contents
-                                       (plist-get input :filename))
-                                      (buffer-string)))
-                              (cons "name" (plist-get input :name))
-                              (cons "filename" (plist-get input :filename))))
-                  values))
+            (when-let ((file (plist-get input :filename)))
+              (push (list "file"
+                          (cons "filedata"
+                                (with-temp-buffer
+                                  (insert-file-contents file)
+                                  (buffer-string)))
+                          (cons "name" name)
+                          (cons "filename" file))
+                    values)))
            ((equal (plist-get input :type) "submit")
             ;; We want the values from buttons if we hit a button if
             ;; we hit enter on it, or if it's the first button after
diff --git a/lisp/net/net-utils.el b/lisp/net/net-utils.el
index 4f68e5db61d..03ed4a59575 100644
--- a/lisp/net/net-utils.el
+++ b/lisp/net/net-utils.el
@@ -563,7 +563,7 @@ This command uses `nslookup-program' to look up DNS records."
            (apply #'vector (mapcar #'string-to-number (split-string ip "\\."))))
           (t (error "Invalid format: %s" format)))))
 
-(defun ipv6-expand (ipv6-vector)
+(defun nslookup--ipv6-expand (ipv6-vector)
   (let ((len (length ipv6-vector)))
     (if (< len 8)
         (let* ((pivot (cl-position 0 ipv6-vector))
@@ -598,9 +598,10 @@ This command uses `nslookup-program' to look up DNS records."
     (cond ((memq format '(string nil))
            ip)
           ((eq format 'vector)
-           (ipv6-expand (apply #'vector
-                               (cl-loop for hextet in (split-string ip "[:]")
-                                        collect (string-to-number hextet 16)))))
+           (nslookup--ipv6-expand
+            (apply #'vector
+                   (cl-loop for hextet in (split-string ip "[:]")
+                            collect (string-to-number hextet 16)))))
           (t (error "Invalid format: %s" format)))))
 
 ;;;###autoload
diff --git a/lisp/net/rfc2104.el b/lisp/net/rfc2104.el
index 5de8401d5b6..fadc979bc15 100644
--- a/lisp/net/rfc2104.el
+++ b/lisp/net/rfc2104.el
@@ -37,8 +37,6 @@
 ;; 64 is block length of hash function (64 for MD5 and SHA), 16 is
 ;; resulting hash length (16 for MD5, 20 for SHA).
 ;;
-;; Tested with Emacs 20.2 and XEmacs 20.3.
-;;
 ;; Test case reference: RFC 2202.
 
 ;;; History:
diff --git a/lisp/net/shr.el b/lisp/net/shr.el
index 81c3fb4aa52..1dff129b9dc 100644
--- a/lisp/net/shr.el
+++ b/lisp/net/shr.el
@@ -1180,8 +1180,24 @@ Return a string with image data."
             ;; so glitches may occur during this transformation.
             (shr-dom-to-xml
              (libxml-parse-xml-region (point) (point-max)))))
+    ;; SVG images often do not have a specified foreground/background
+    ;; color, so wrap them in styles.
+    (when (eq content-type 'image/svg+xml)
+      (setq data (svg--wrap-svg data)))
     (list data content-type)))
 
+(defun svg--wrap-svg (data)
+  "Add a default foreground colour to SVG images."
+  (with-temp-buffer
+    (insert "<svg xmlns:xlink=\"http://www.w3.org/1999/xlink\" "
+            "xmlns:xi=\"http://www.w3.org/2001/XInclude\" "
+            "style=\"color: "
+            (face-foreground 'default) ";\">"
+            "<xi:include href=\"data:image/svg+xml;base64,"
+            (base64-encode-string data t)
+            "\"></xi:include></svg>")
+    (buffer-string)))
+
 (defun shr-image-displayer (content-function)
   "Return a function to display an image.
 CONTENT-FUNCTION is a function to retrieve an image for a cid url that
diff --git a/lisp/net/tramp-adb.el b/lisp/net/tramp-adb.el
index df4778c9c96..982522bdaf4 100644
--- a/lisp/net/tramp-adb.el
+++ b/lisp/net/tramp-adb.el
@@ -1191,6 +1191,10 @@ FMT and ARGS are passed to `error'."
   "Maybe open a connection VEC.
 Does not do anything if a connection is already open, but re-opens the
 connection if a previous connection has died for some reason."
+  ;; During completion, don't reopen a new connection.
+  (unless (tramp-connectable-p vec)
+    (throw 'non-essential 'non-essential))
+
   (let* ((buf (tramp-get-connection-buffer vec))
          (p (get-buffer-process buf))
          (host (tramp-file-name-host vec))
@@ -1204,14 +1208,6 @@ connection if a previous connection has died for some reason."
       (tramp-error vec 'file-error "Cannot switch to user `%s'" user))
 
     (unless (process-live-p p)
-      ;; During completion, don't reopen a new connection.  We check
-      ;; this for the process related to `tramp-buffer-name';
-      ;; otherwise `start-file-process' wouldn't run ever when
-      ;; `non-essential' is non-nil.
-      (when (and (tramp-completion-mode-p)
-                 (null (get-process (tramp-buffer-name vec))))
-        (throw 'non-essential 'non-essential))
-
       (save-match-data
         (when (and p (processp p)) (delete-process p))
         (if (zerop (length device))
diff --git a/lisp/net/tramp-gvfs.el b/lisp/net/tramp-gvfs.el
index b9b6b4b6d18..1036865e4ec 100644
--- a/lisp/net/tramp-gvfs.el
+++ b/lisp/net/tramp-gvfs.el
@@ -1787,6 +1787,10 @@ This is relevant for GNOME Online Accounts."
   "Maybe open a connection VEC.
 Does not do anything if a connection is already open, but re-opens the
 connection if a previous connection has died for some reason."
+  ;; During completion, don't reopen a new connection.
+  (unless (tramp-connectable-p vec)
+    (throw 'non-essential 'non-essential))
+
   ;; We set the file name, in case there are incoming D-Bus signals or
   ;; D-Bus errors.
   (setq tramp-gvfs-dbus-event-vector vec)
diff --git a/lisp/net/tramp-rclone.el b/lisp/net/tramp-rclone.el
index 866e7791bf8..1f0c7eadbc5 100644
--- a/lisp/net/tramp-rclone.el
+++ b/lisp/net/tramp-rclone.el
@@ -520,19 +520,14 @@ file names."
   "Maybe open a connection VEC.
 Does not do anything if a connection is already open, but re-opens the
 connection if a previous connection has died for some reason."
+  ;; During completion, don't reopen a new connection.
+  (unless (tramp-connectable-p vec)
+    (throw 'non-essential 'non-essential))
+
   (let ((host (tramp-file-name-host vec)))
     (when (rassoc `(,host) (tramp-rclone-parse-device-names nil))
       (if (zerop (length host))
           (tramp-error vec 'file-error "Storage %s not connected" host))
-
-      ;; During completion, don't reopen a new connection.  We check
-      ;; this for the process related to `tramp-buffer-name';
-      ;; otherwise `start-file-process' wouldn't run ever when
-      ;; `non-essential' is non-nil.
-      (when (and (tramp-completion-mode-p)
-                 (null (get-process (tramp-buffer-name vec))))
-        (throw 'non-essential 'non-essential))
-
       ;; We need a process bound to the connection buffer.  Therefore,
       ;; we create a dummy process.  Maybe there is a better solution?
       (unless (get-buffer-process (tramp-get-connection-buffer vec))
diff --git a/lisp/net/tramp-sh.el b/lisp/net/tramp-sh.el
index bcfac78ee65..8092f6a5cf1 100644
--- a/lisp/net/tramp-sh.el
+++ b/lisp/net/tramp-sh.el
@@ -525,7 +525,9 @@ based on the Tramp and Emacs versions, and should not be set here."
   :type '(repeat string))
 
 ;;;###tramp-autoload
-(defcustom tramp-sh-extra-args '(("/bash\\'" . "-norc -noprofile"))
+(defcustom tramp-sh-extra-args
+  '(("/bash\\'" . "-norc -noprofile")
+    ("/zsh\\'" . "-f +Z"))
   "Alist specifying extra arguments to pass to the remote shell.
 Entries are (REGEXP . ARGS) where REGEXP is a regular expression
 matching the shell file name and ARGS is a string specifying the
@@ -1198,18 +1200,22 @@ component is used as the target of the symlink."
 
 (defun tramp-sh-handle-file-exists-p (filename)
   "Like `file-exists-p' for Tramp files."
-  (with-parsed-tramp-file-name filename nil
-    (with-tramp-file-property v localname "file-exists-p"
-      (or (not (null (tramp-get-file-property
-                      v localname "file-attributes-integer" nil)))
-          (not (null (tramp-get-file-property
-                      v localname "file-attributes-string" nil)))
-          (tramp-send-command-and-check
-           v
-           (format
-            "%s %s"
-            (tramp-get-file-exists-command v)
-            (tramp-shell-quote-argument localname)))))))
+  ;; `file-exists-p' is used as predicate in file name completion.
+  ;; We don't want to run it when `non-essential' is t, or there is
+  ;; no connection process yet.
+  (when (tramp-connectable-p filename)
+    (with-parsed-tramp-file-name filename nil
+      (with-tramp-file-property v localname "file-exists-p"
+        (or (not (null (tramp-get-file-property
+                        v localname "file-attributes-integer" nil)))
+            (not (null (tramp-get-file-property
+                        v localname "file-attributes-string" nil)))
+            (tramp-send-command-and-check
+             v
+             (format
+              "%s %s"
+              (tramp-get-file-exists-command v)
+              (tramp-shell-quote-argument localname))))))))
 
 (defun tramp-sh-handle-file-attributes (filename &optional id-format)
   "Like `file-attributes' for Tramp files."
@@ -4762,6 +4768,10 @@ If there is just some editing, retry it after 5 seconds."
   "Maybe open a connection VEC.
 Does not do anything if a connection is already open, but re-opens the
 connection if a previous connection has died for some reason."
+  ;; During completion, don't reopen a new connection.
+  (unless (tramp-connectable-p vec)
+    (throw 'non-essential 'non-essential))
+
   (let ((p (tramp-get-connection-process vec))
         (process-name (tramp-get-connection-property vec "process-name" nil))
         (process-environment (copy-sequence process-environment))
@@ -4806,15 +4816,6 @@ connection if a previous connection has died for some reason."
     ;; New connection must be opened.
     (condition-case err
         (unless (process-live-p p)
-
-          ;; During completion, don't reopen a new connection.  We
-          ;; check this for the process related to
-          ;; `tramp-buffer-name'; otherwise `start-file-process'
-          ;; wouldn't run ever when `non-essential' is non-nil.
-          (when (and (tramp-completion-mode-p)
-                     (null (get-process (tramp-buffer-name vec))))
-            (throw 'non-essential 'non-essential))
-
           (with-tramp-progress-reporter
               vec 3
               (if (zerop (length (tramp-file-name-user vec)))
diff --git a/lisp/net/tramp-smb.el b/lisp/net/tramp-smb.el
index 5df26a1e33e..b008e6b25eb 100644
--- a/lisp/net/tramp-smb.el
+++ b/lisp/net/tramp-smb.el
@@ -832,12 +832,12 @@ PRESERVE-UID-GID and PRESERVE-EXTENDED-ATTRIBUTES are completely ignored."
   "Implement `file-attributes' for Tramp files using stat command."
   (tramp-message
    vec 5 "file attributes with stat: %s" (tramp-file-name-localname vec))
-  (with-current-buffer (tramp-get-connection-buffer vec)
-    (let* (size id link uid gid atime mtime ctime mode inode)
-      (when (tramp-smb-send-command
-             vec (format "stat \"%s\"" (tramp-smb-get-localname vec)))
+  (let* (size id link uid gid atime mtime ctime mode inode)
+    (when (tramp-smb-send-command
+           vec (format "stat \"%s\"" (tramp-smb-get-localname vec)))
 
-        ;; Loop the listing.
+      ;; Loop the listing.
+      (with-current-buffer (tramp-get-connection-buffer vec)
         (goto-char (point-min))
         (unless (re-search-forward tramp-smb-errors nil t)
           (while (not (eobp))
@@ -1628,40 +1628,40 @@ Result is a list of (LOCALNAME MODE SIZE MONTH DAY TIME YEAR)."
   (with-parsed-tramp-file-name (file-name-as-directory directory) nil
     (setq localname (or localname "/"))
     (with-tramp-file-property v localname "file-entries"
-      (with-current-buffer (tramp-get-connection-buffer v)
-        (let* ((share (tramp-smb-get-share v))
-               (cache (tramp-get-connection-property v "share-cache" nil))
-               res entry)
-
-          (if (and (not share) cache)
-              ;; Return cached shares.
-              (setq res cache)
-
-            ;; Read entries.
-            (if share
-                (tramp-smb-send-command
-                 v (format "dir \"%s*\"" (tramp-smb-get-localname v)))
-              ;; `tramp-smb-maybe-open-connection' lists also the share names.
-              (tramp-smb-maybe-open-connection v))
-
-            ;; Loop the listing.
+      (let* ((share (tramp-smb-get-share v))
+             (cache (tramp-get-connection-property v "share-cache" nil))
+             res entry)
+
+        (if (and (not share) cache)
+            ;; Return cached shares.
+            (setq res cache)
+
+          ;; Read entries.
+          (if share
+              (tramp-smb-send-command
+               v (format "dir \"%s*\"" (tramp-smb-get-localname v)))
+            ;; `tramp-smb-maybe-open-connection' lists also the share names.
+            (tramp-smb-maybe-open-connection v))
+
+          ;; Loop the listing.
+          (with-current-buffer (tramp-get-connection-buffer v)
             (goto-char (point-min))
             (if (re-search-forward tramp-smb-errors nil t)
                 (tramp-error v 'file-error "%s `%s'" (match-string 0) directory)
               (while (not (eobp))
                 (setq entry (tramp-smb-read-file-entry share))
                 (forward-line)
-                (when entry (push entry res))))
+                (when entry (push entry res)))))
 
-            ;; Cache share entries.
-            (unless share
-              (tramp-set-connection-property v "share-cache" res)))
+          ;; Cache share entries.
+          (unless share
+            (tramp-set-connection-property v "share-cache" res)))
 
-          ;; Add directory itself.
-          (push '("" "drwxrwxrwx" 0 (0 0)) res)
+        ;; Add directory itself.
+        (push '("" "drwxrwxrwx" 0 (0 0)) res)
 
-          ;; Return entries.
-          (delq nil res))))))
+        ;; Return entries.
+        (delq nil res)))))
 
 ;; Return either a share name (if SHARE is nil), or a file name.
 ;;
@@ -1855,6 +1855,10 @@ Does not do anything if a connection is already open, but re-opens the
 connection if a previous connection has died for some reason.
 If ARGUMENT is non-nil, use it as argument for
 `tramp-smb-winexe-program', and suppress any checks."
+  ;; During completion, don't reopen a new connection.
+  (unless (tramp-connectable-p vec)
+    (throw 'non-essential 'non-essential))
+
   (let* ((share (tramp-smb-get-share vec))
          (buf (tramp-get-connection-buffer vec))
          (p (get-buffer-process buf)))
@@ -1909,15 +1913,6 @@ If ARGUMENT is non-nil, use it as argument for
                      (string-equal
                       share
                       (tramp-get-connection-property p "smb-share" ""))))
-
-      ;; During completion, don't reopen a new connection.  We
-      ;; check this for the process related to
-      ;; `tramp-buffer-name'; otherwise `start-file-process'
-      ;; wouldn't run ever when `non-essential' is non-nil.
-      (when (and (tramp-completion-mode-p)
-                 (null (get-process (tramp-buffer-name vec))))
-        (throw 'non-essential 'non-essential))
-
       (save-match-data
         ;; There might be unread output from checking for share names.
         (when buf (with-current-buffer buf (erase-buffer)))
diff --git a/lisp/net/tramp-sudoedit.el b/lisp/net/tramp-sudoedit.el
index 80ce8f78747..bfc9b3bdc3a 100644
--- a/lisp/net/tramp-sudoedit.el
+++ b/lisp/net/tramp-sudoedit.el
@@ -424,10 +424,14 @@ the result will be a local, non-Tramp, file name."
 
 (defun tramp-sudoedit-handle-file-exists-p (filename)
   "Like `file-exists-p' for Tramp files."
-  (with-parsed-tramp-file-name filename nil
-    (with-tramp-file-property v localname "file-exists-p"
-      (tramp-sudoedit-send-command
-       v "test" "-e" (tramp-compat-file-name-unquote localname)))))
+  ;; `file-exists-p' is used as predicate in file name completion.
+  ;; We don't want to run it when `non-essential' is t, or there is
+  ;; no connection process yet.
+  (when (tramp-connectable-p filename)
+    (with-parsed-tramp-file-name filename nil
+      (with-tramp-file-property v localname "file-exists-p"
+        (tramp-sudoedit-send-command
+         v "test" "-e" (tramp-compat-file-name-unquote localname))))))
 
 (defun tramp-sudoedit-handle-file-name-all-completions (filename directory)
   "Like `file-name-all-completions' for Tramp files."
@@ -760,18 +764,13 @@ Remove unneeded output."
   "Maybe open a connection VEC.
 Does not do anything if a connection is already open, but re-opens the
 connection if a previous connection has died for some reason."
+  ;; During completion, don't reopen a new connection.
+  (unless (tramp-connectable-p vec)
+    (throw 'non-essential 'non-essential))
+
   ;; We need a process bound to the connection buffer.  Therefore, we
   ;; create a dummy process.  Maybe there is a better solution?
   (unless (tramp-get-connection-process vec)
-
-    ;; During completion, don't reopen a new connection.  We check
-    ;; this for the process related to `tramp-buffer-name'; otherwise
-    ;; `start-file-process' wouldn't run ever when `non-essential' is
-    ;; non-nil.
-    (when (and (tramp-completion-mode-p)
-               (null (get-process (tramp-buffer-name vec))))
-      (throw 'non-essential 'non-essential))
-
     (let ((p (make-network-process
               :name (tramp-get-connection-name vec)
               :buffer (tramp-get-connection-buffer vec)
diff --git a/lisp/net/tramp.el b/lisp/net/tramp.el
index ed0f1def181..aefb84bb4e4 100644
--- a/lisp/net/tramp.el
+++ b/lisp/net/tramp.el
@@ -1566,25 +1566,27 @@ necessary only.  This function will be used in file name completion."
              tramp-postfix-host-format))
           (when localname localname)))
 
-(defun tramp-get-buffer (vec)
+(defun tramp-get-buffer (vec &optional dont-create)
   "Get the connection buffer to be used for VEC."
   (or (get-buffer (tramp-buffer-name vec))
-      (with-current-buffer (get-buffer-create (tramp-buffer-name vec))
-        ;; We use the existence of connection property "process-buffer"
-        ;; as indication, whether a connection is active.
-        (tramp-set-connection-property
-         vec "process-buffer"
-         (tramp-get-connection-property vec "process-buffer" nil))
-        (setq buffer-undo-list t
-              default-directory (tramp-make-tramp-file-name vec 'noloc 'nohop))
-        (current-buffer))))
-
-(defun tramp-get-connection-buffer (vec)
+      (unless dont-create
+        (with-current-buffer (get-buffer-create (tramp-buffer-name vec))
+          ;; We use the existence of connection property "process-buffer"
+          ;; as indication, whether a connection is active.
+          (tramp-set-connection-property
+           vec "process-buffer"
+           (tramp-get-connection-property vec "process-buffer" nil))
+          (setq buffer-undo-list t
+                default-directory
+                (tramp-make-tramp-file-name vec 'noloc 'nohop))
+          (current-buffer)))))
+
+(defun tramp-get-connection-buffer (vec &optional dont-create)
   "Get the connection buffer to be used for VEC.
 In case a second asynchronous communication has been started, it is different
 from `tramp-get-buffer'."
   (or (tramp-get-connection-property vec "process-buffer" nil)
-      (tramp-get-buffer vec)))
+      (tramp-get-buffer vec dont-create)))
 
 (defun tramp-get-connection-name (vec)
   "Get the connection name to be used for VEC.
@@ -1770,14 +1772,15 @@ applicable)."
       ;; Log only when there is a minimum level.
       (when (>= tramp-verbose 4)
         (let ((tramp-verbose 0))
-          ;; Append connection buffer for error messages.
+          ;; Append connection buffer for error messages, if exists.
           (when (= level 1)
-            (with-current-buffer
-                (if (processp vec-or-proc)
-                    (process-buffer vec-or-proc)
-                  (tramp-get-connection-buffer vec-or-proc))
-              (setq fmt-string (concat fmt-string "\n%s")
-                    arguments (append arguments (list (buffer-string))))))
+            (ignore-errors
+              (with-current-buffer
+                  (if (processp vec-or-proc)
+                      (process-buffer vec-or-proc)
+                    (tramp-get-connection-buffer vec-or-proc 'dont-create))
+                (setq fmt-string (concat fmt-string "\n%s")
+                      arguments (append arguments (list (buffer-string)))))))
           ;; Translate proc to vec.
           (when (processp vec-or-proc)
             (setq vec-or-proc (process-get vec-or-proc 'vector))))
@@ -2517,16 +2520,21 @@ Add operations defined in `HANDLER-alist' to `tramp-file-name-handler'."
    ;; This variable has been obsoleted in Emacs 26.
    tramp-completion-mode))
 
-(defun tramp-connectable-p (filename)
+(defun tramp-connectable-p (vec-or-filename)
   "Check, whether it is possible to connect the remote host w/o side-effects.
 This is true, if either the remote host is already connected, or if we are
 not in completion mode."
-  (let (tramp-verbose)
-    (and (tramp-tramp-file-p filename)
-         (or (not (tramp-completion-mode-p))
-             (process-live-p
-              (tramp-get-connection-process
-               (tramp-dissect-file-name filename)))))))
+  (let (tramp-verbose
+        (vec
+         (cond
+          ((tramp-file-name-p vec-or-filename) vec-or-filename)
+          ((tramp-tramp-file-p vec-or-filename)
+           (tramp-dissect-file-name vec-or-filename)))))
+    (or ;; We check this for the process related to
+        ;; `tramp-buffer-name'; otherwise `start-file-process'
+        ;; wouldn't run ever when `non-essential' is non-nil.
+        (and vec (process-live-p (get-process (tramp-buffer-name vec))))
+        (not (tramp-completion-mode-p)))))
 
 ;; Method, host name and user name completion.
 ;; `tramp-completion-dissect-file-name' returns a list of
@@ -2606,8 +2614,7 @@ not in completion mode."
   (try-completion
    filename
    (mapcar #'list (file-name-all-completions filename directory))
-   (when (and predicate
-              (tramp-connectable-p (expand-file-name filename directory)))
+   (when (and predicate (tramp-connectable-p directory))
      (lambda (x) (funcall predicate (expand-file-name (car x) directory))))))
 
 ;; I misuse a little bit the `tramp-file-name' structure in order to
@@ -3096,7 +3103,11 @@ User is always nil."
 
 (defun tramp-handle-file-exists-p (filename)
   "Like `file-exists-p' for Tramp files."
-  (not (null (file-attributes filename))))
+  ;; `file-exists-p' is used as predicate in file name completion.
+  ;; We don't want to run it when `non-essential' is t, or there is
+  ;; no connection process yet.
+  (when (tramp-connectable-p filename)
+    (not (null (file-attributes filename)))))
 
 (defun tramp-handle-file-in-directory-p (filename directory)
   "Like `file-in-directory-p' for Tramp files."
diff --git a/lisp/play/gamegrid.el b/lisp/play/gamegrid.el
index be09a73a1f1..df9b1352480 100644
--- a/lisp/play/gamegrid.el
+++ b/lisp/play/gamegrid.el
@@ -505,9 +505,12 @@ format."
 
 ;; ;;;;;;;;;;;;;;; high score functions ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
-(defun gamegrid-add-score (file score)
+(defun gamegrid-add-score (file score &optional reverse)
   "Add the current score to the high score file.
 
+If REVERSE is non-nil, treat lower scores as better than higher
+scores. This is useful for games where lower scores are better.
+
 On POSIX systems there may be a shared game directory for all users in
 which the scorefiles are kept.  On such systems Emacs doesn't create
 the score file FILE in this directory, if it doesn't already exist.
@@ -525,9 +528,9 @@ specified by the variable `temporary-file-directory'.  If necessary,
 FILE is created there."
   (pcase system-type
     ((or 'ms-dos 'windows-nt)
-     (gamegrid-add-score-insecure file score))
+     (gamegrid-add-score-insecure file score reverse))
     (_
-     (gamegrid-add-score-with-update-game-score file score))))
+     (gamegrid-add-score-with-update-game-score file score reverse))))
 
 
 ;; On POSIX systems there are four cases to distinguish:
@@ -556,20 +559,21 @@ FILE is created there."
 
 (defvar gamegrid-shared-game-dir)
 
-(defun gamegrid-add-score-with-update-game-score (file score)
+(defun gamegrid-add-score-with-update-game-score (file score &optional reverse)
   (let* ((update-game-score-modes
           (file-modes (expand-file-name "update-game-score" exec-directory)))
          (gamegrid-shared-game-dir
           (not (zerop (logand #o6000 (or update-game-score-modes 0))))))
     (cond ((or (not update-game-score-modes) (file-name-absolute-p file))
            (gamegrid-add-score-insecure file score
-                                        gamegrid-user-score-file-directory))
+                                        gamegrid-user-score-file-directory
+                                        reverse))
           ((and gamegrid-shared-game-dir
                 (file-exists-p (expand-file-name file shared-game-score-directory)))
            ;; Use the setgid (or setuid) "update-game-score" program
            ;; to update a system-wide score file.
            (gamegrid-add-score-with-update-game-score-1 file
-            (expand-file-name file shared-game-score-directory) score))
+            (expand-file-name file shared-game-score-directory) score reverse))
           ;; Else: Add the score to a score file in the user's home
           ;; directory.
           (gamegrid-shared-game-dir
@@ -579,7 +583,8 @@ FILE is created there."
                     (directory-file-name gamegrid-user-score-file-directory))
              (make-directory gamegrid-user-score-file-directory t))
            (gamegrid-add-score-insecure file score
-                                        gamegrid-user-score-file-directory))
+                                        gamegrid-user-score-file-directory
+                                        reverse))
           (t
            (unless (file-exists-p
                     (directory-file-name gamegrid-user-score-file-directory))
@@ -588,9 +593,9 @@ FILE is created there."
                                       gamegrid-user-score-file-directory)))
              (unless (file-exists-p f)
                (write-region "" nil f nil 'silent nil 'excl))
-             (gamegrid-add-score-with-update-game-score-1 file f score))))))
+             (gamegrid-add-score-with-update-game-score-1 file f score reverse))))))
 
-(defun gamegrid-add-score-with-update-game-score-1 (file target score)
+(defun gamegrid-add-score-with-update-game-score-1 (file target score &optional reverse)
   (let ((default-directory "/")
         (errbuf (generate-new-buffer " *update-game-score loss*"))
         (marker-string (concat
@@ -601,17 +606,16 @@ FILE is created there."
     (with-local-quit
       (apply
        'call-process
-       (append
-        (list
-         (expand-file-name "update-game-score" exec-directory)
-         nil errbuf nil
-         "-m" (int-to-string gamegrid-score-file-length)
-         "-d" (if gamegrid-shared-game-dir
-                  (expand-file-name shared-game-score-directory)
-                (file-name-directory target))
-         file
-         (int-to-string score)
-         marker-string))))
+       `(,(expand-file-name "update-game-score" exec-directory)
+         nil ,errbuf nil
+         "-m" ,(int-to-string gamegrid-score-file-length)
+         "-d" ,(if gamegrid-shared-game-dir
+                   (expand-file-name shared-game-score-directory)
+                 (file-name-directory target))
+         ,@(if reverse '("-r"))
+         ,file
+         ,(int-to-string score)
+         ,marker-string)))
     (if (buffer-modified-p errbuf)
         (progn
           (display-buffer errbuf)
@@ -632,7 +636,7 @@ FILE is created there."
                                 marker-string) nil t)
         (beginning-of-line)))))
 
-(defun gamegrid-add-score-insecure (file score &optional directory)
+(defun gamegrid-add-score-insecure (file score &optional directory reverse)
   (save-excursion
     (setq file (expand-file-name file (or directory
                                           temporary-file-directory)))
@@ -645,7 +649,8 @@ FILE is created there."
                     (user-full-name)
                     user-mail-address))
     (sort-fields 1 (point-min) (point-max))
-    (reverse-region (point-min) (point-max))
+    (unless reverse
+      (reverse-region (point-min) (point-max)))
     (goto-char (point-min))
     (forward-line gamegrid-score-file-length)
     (delete-region (point) (point-max))
diff --git a/lisp/progmodes/python.el b/lisp/progmodes/python.el
index 14b65669c4b..ec5d8c55512 100644
--- a/lisp/progmodes/python.el
+++ b/lisp/progmodes/python.el
@@ -4084,6 +4084,12 @@ JUSTIFY should be used (if applicable) as in `fill-paragraph'."
       (goto-char (line-end-position))))
   t)
 
+(defun python-do-auto-fill ()
+  "Like `do-auto-fill', but bind `fill-indent-according-to-mode'."
+  ;; See Bug#36056.
+  (let ((fill-indent-according-to-mode t))
+    (do-auto-fill)))
+
 
 ;;; Skeletons
 
@@ -5379,7 +5385,7 @@ REPORT-FN is Flymake's callback function."
   (set (make-local-variable 'paragraph-start) "\\s-*$")
   (set (make-local-variable 'fill-paragraph-function)
        #'python-fill-paragraph)
-  (set (make-local-variable 'fill-indent-according-to-mode) t) ; Bug#36056.
+  (set (make-local-variable 'normal-auto-fill-function) #'python-do-auto-fill)
 
   (set (make-local-variable 'beginning-of-defun-function)
        #'python-nav-beginning-of-defun)
diff --git a/lisp/progmodes/sh-script.el b/lisp/progmodes/sh-script.el
index aad38b94d76..cbc0ac74f09 100644
--- a/lisp/progmodes/sh-script.el
+++ b/lisp/progmodes/sh-script.el
@@ -112,7 +112,7 @@
 ;; would make this unnecessary;  simply learn the values when you visit
 ;; the buffer.
 ;; You can do this automatically like this:
-;;   (add-hook 'sh-set-shell-hook 'sh-learn-buffer-indent)
+;;   (add-hook 'sh-set-shell-hook #'sh-learn-buffer-indent)
 ;;
 ;; However...  `sh-learn-buffer-indent' is extremely slow,
 ;; especially on large-ish buffer.  Also, if there are conflicts the
@@ -480,7 +480,6 @@ This is buffer-local in every such buffer.")
     (define-key map "\C-c>" 'sh-learn-buffer-indent)
     (define-key map "\C-c\C-\\" 'sh-backslash-region)
 
-    (define-key map "=" 'sh-assignment)
     (define-key map "\C-c+" 'sh-add)
     (define-key map "\C-\M-x" 'sh-execute-region)
     (define-key map "\C-c\C-x" 'executable-interpret)
@@ -1059,7 +1058,7 @@ subshells can nest."
       (when (< startpos (line-beginning-position))
         (put-text-property startpos (point) 'syntax-multiline t)
         (add-hook 'syntax-propertize-extend-region-functions
-                  'syntax-propertize-multiline nil t))
+                  #'syntax-propertize-multiline nil t))
       )))
 
 
@@ -1603,25 +1602,25 @@ with your script for an edit-interpret-debug cycle."
   (setq-local local-abbrev-table sh-mode-abbrev-table)
   (setq-local comint-dynamic-complete-functions
               sh-dynamic-complete-functions)
-  (add-hook 'completion-at-point-functions 'comint-completion-at-point nil t)
+  (add-hook 'completion-at-point-functions #'comint-completion-at-point nil t)
   ;; we can't look if previous line ended with `\'
   (setq-local comint-prompt-regexp "^[ \t]*")
   (setq-local imenu-case-fold-search nil)
   (setq font-lock-defaults
-        '((sh-font-lock-keywords
+        `((sh-font-lock-keywords
            sh-font-lock-keywords-1 sh-font-lock-keywords-2)
           nil nil
           ((?/ . "w") (?~ . "w") (?. . "w") (?- . "w") (?_ . "w")) nil
           (font-lock-syntactic-face-function
-           . sh-font-lock-syntactic-face-function)))
+           . ,#'sh-font-lock-syntactic-face-function)))
   (setq-local syntax-propertize-function #'sh-syntax-propertize-function)
   (add-hook 'syntax-propertize-extend-region-functions
             #'syntax-propertize-multiline 'append 'local)
   (setq-local skeleton-pair-alist '((?` _ ?`)))
-  (setq-local skeleton-pair-filter-function 'sh-quoted-p)
+  (setq-local skeleton-pair-filter-function #'sh-quoted-p)
   (setq-local skeleton-further-elements
               '((< '(- (min sh-basic-offset (current-column))))))
-  (setq-local skeleton-filter-function 'sh-feature)
+  (setq-local skeleton-filter-function #'sh-feature)
   (setq-local skeleton-newline-indent-rigidly t)
   (setq-local defun-prompt-regexp
               (concat
@@ -2408,12 +2407,12 @@ whose value is the shell name (don't quote it)."
           (message "setting up indent stuff")
           ;; sh-mode has already made indent-line-function local
           ;; but do it in case this is called before that.
-          (setq-local indent-line-function 'sh-indent-line))
+          (setq-local indent-line-function #'sh-indent-line))
         (if sh-make-vars-local
             (sh-make-vars-local))
         (message "Indentation setup for shell type %s" sh-shell))
     (message "No indentation for this shell type.")
-    (setq-local indent-line-function 'sh-basic-indent-line))
+    (setq-local indent-line-function #'sh-basic-indent-line))
   (when font-lock-mode
     (setq font-lock-set-defaults nil)
     (font-lock-set-defaults)
@@ -3586,7 +3585,7 @@ so that `occur-next' and `occur-prev' will work."
 ;;       (insert ")\n")
 ;;       )))
 ;;
-;; (add-hook 'sh-learned-buffer-hook 'what-i-learned)
+;; (add-hook 'sh-learned-buffer-hook #'what-i-learned)
 
 
 ;; Originally this was sh-learn-region-indent (beg end)
@@ -4055,7 +4054,8 @@ Add these variables to `sh-shell-variables'."
     (goto-char (point-min))
     (setq sh-shell-variables-initialized t)
     (while (search-forward "=" nil t)
-      (sh-assignment 0)))
+      (sh--assignment-collect)))
+  (add-hook 'post-self-insert-hook #'sh--assignment-collect nil t)
   (message "Scanning buffer `%s' for variable assignments...done"
            (buffer-name)))
 
@@ -4328,20 +4328,24 @@ option followed by a colon `:' if the option accepts an argument."
 
 
 
+(put 'sh-assignment 'delete-selection t)
 (defun sh-assignment (arg)
   "Remember preceding identifier for future completion and do self-insert."
   (interactive "p")
+  (declare (obsolete nil "27.1"))
   (self-insert-command arg)
-  (if (<= arg 1)
-      (sh-remember-variable
-       (save-excursion
-         (if (re-search-forward (sh-feature sh-assignment-regexp)
-                                (prog1 (point)
-                                  (beginning-of-line 1))
-                                t)
-             (match-string 1))))))
+  (sh--assignment-collect))
+
+(defun sh--assignment-collect ()
+  (sh-remember-variable
+   (when (eq ?= (char-before))
+     (save-excursion
+       (if (re-search-forward (sh-feature sh-assignment-regexp)
+                              (prog1 (point)
+                                (beginning-of-line 1))
+                              t)
+           (match-string 1))))))
 
-(put 'sh-assignment 'delete-selection t)
 
 (defun sh-maybe-here-document (arg)
   "Insert self.  Without prefix, following unquoted `<' inserts here document.
diff --git a/lisp/replace.el b/lisp/replace.el
index ad9be77a79b..5c0616e25f0 100644
--- a/lisp/replace.el
+++ b/lisp/replace.el
@@ -2698,7 +2698,7 @@ characters."
                                  (num-replacements  0)
                                  (nocasify t) ; Undo must preserve case (Bug#31073).
                                  search-string
-                                 next-replacement)
+                                 last-replacement)
                              (while (and (< stack-idx stack-len)
                                          stack
                                          (or (null replaced) last-was-act-and-show))
@@ -2709,9 +2709,9 @@ characters."
                                   ;; Bind swapped values
                                   ;; (search-string <--> replacement)
                                   search-string (nth (if replaced 4 3) elt)
-                                  next-replacement (nth (if replaced 3 4) elt)
+                                  last-replacement (nth (if replaced 3 4) elt)
                                   search-string-replaced search-string
-                                  next-replacement-replaced next-replacement
+                                  next-replacement-replaced last-replacement
                                   last-was-act-and-show nil)
 
                                  (when (and (= stack-idx stack-len)
@@ -2733,16 +2733,18 @@ characters."
                                            (match-data t (nth 2 elt)))
                                          noedit
                                          (replace-match-maybe-edit
-                                          next-replacement nocasify literal
+                                          last-replacement nocasify literal
                                           noedit real-match-data backward)
                                          replace-count (1- replace-count)
                                          real-match-data
                                          (save-excursion
                                            (goto-char (match-beginning 0))
                                            (if regexp-flag
-                                               (looking-at next-replacement)
-                                             (looking-at (regexp-quote next-replacement)))
+                                               (looking-at last-replacement)
+                                             (looking-at (regexp-quote last-replacement)))
                                            (match-data t (nth 2 elt))))
+                                   (when regexp-flag
+                                     (setq next-replacement (nth 4 elt)))
                                    ;; Set replaced nil to keep in loop
                                    (when (eq def 'undo-all)
                                      (setq replaced nil
diff --git a/lisp/select.el b/lisp/select.el
index 59bcf7da664..334e10f41ba 100644
--- a/lisp/select.el
+++ b/lisp/select.el
@@ -160,12 +160,11 @@ The value nil is the same as the list (UTF8_STRING COMPOUND_TEXT STRING)."
                       (const TEXT)))
   :group 'killing)
 
-;; Get a selection value of type TYPE by calling gui-get-selection with
-;; an appropriate DATA-TYPE argument decided by `x-select-request-type'.
-;; The return value is already decoded.  If gui-get-selection causes an
-;; error, this function return nil.
-
 (defun gui--selection-value-internal (type)
+  "Get a selection value of type TYPE.
+Call `gui-get-selection' with an appropriate DATA-TYPE argument
+decided by `x-select-request-type'.  The return value is already
+decoded.  If `gui-get-selection' signals an error, return nil."
   (let ((request-type (if (eq window-system 'x)
                           (or x-select-request-type
                               '(UTF8_STRING COMPOUND_TEXT STRING))
diff --git a/lisp/server.el b/lisp/server.el
index ac81cdbd483..45fa55ad6b0 100644
--- a/lisp/server.el
+++ b/lisp/server.el
@@ -563,9 +563,9 @@ See variable `server-auth-dir' for details."
                      (format "it is not owned by you (owner = %s (%d))"
                              (user-full-name uid) uid))
                     (w32 nil)           ; on NTFS?
-                    ((/= 0 (logand ?\077 (file-modes dir)))
-                     (format "it is accessible by others (%03o)"
-                             (file-modes dir)))
+                    ((let ((modes (file-modes dir)))
+                       (unless (zerop (logand (or modes 0) #o077))
+                         (format "it is accessible by others (%03o)" modes))))
                     (t nil))))
       (when unsafe
         (error "`%s' is not a safe directory because %s"
diff --git a/lisp/shadowfile.el b/lisp/shadowfile.el
index 2778e583674..72491b99807 100644
--- a/lisp/shadowfile.el
+++ b/lisp/shadowfile.el
@@ -207,7 +207,7 @@ PREFIX."
 
 ;;; I use the term `site' to refer to a string which may be the
 ;;; cluster identification "/name:", a remote identification
-;;; "/method:user@host:", or "/system-name:' (the value of
+;;; "/method:user@host:", or "/system-name:" (the value of
 ;;; `shadow-system-name') for the location of local files.  All
 ;;; user-level commands should accept either.
 
@@ -607,6 +607,11 @@ and to are absolute file names."
                         canonical-file shadow-literal-groups nil)
                        (shadow-shadows-of-1
                         canonical-file shadow-regexp-groups t)))))
+          (when shadow-debug
+            (message
+             "shadow-shadows-of: %s %s %s %s %s"
+             file (shadow-local-file file) shadow-homedir
+             absolute-file canonical-file))
         (set (intern file shadow-hashtable) shadows))))
 
 (defun shadow-shadows-of-1 (file groups regexp)
@@ -621,6 +626,10 @@ Consider them as regular expressions if third arg REGEXP is true."
                        (let ((realname
                               (tramp-file-name-localname
                                (shadow-parse-name file))))
+                         (when shadow-debug
+                           (message
+                            "shadow-shadows-of-1: %s %s %s"
+                            file (shadow-parse-name file) realname))
                          (mapcar
                           (function
                            (lambda (x)
@@ -631,6 +640,11 @@ Consider them as regular expressions if third arg REGEXP is true."
 
 (defun shadow-add-to-todo ()
   "If current buffer has shadows, add them to the list needing to be copied."
+  (when shadow-debug
+    (message
+     "shadow-add-to-todo: %s %s"
+     (buffer-file-name (current-buffer))
+     (shadow-expand-file-name (buffer-file-name (current-buffer)))))
   (let ((shadows (shadow-shadows-of
                   (shadow-expand-file-name
                    (buffer-file-name (current-buffer))))))
diff --git a/lisp/startup.el b/lisp/startup.el
index a16db242da0..ef6234128aa 100644
--- a/lisp/startup.el
+++ b/lisp/startup.el
@@ -406,6 +406,7 @@ if you have not already set `auto-save-list-file-name' yourself.
 Directories in the prefix will be created if necessary.
 Set this to nil if you want to prevent `auto-save-list-file-name'
 from being initialized."
+  :initialize #'custom-initialize-delay
   :type '(choice (const :tag "Don't record a session's auto save list" nil)
                  string)
   :group 'auto-save)
diff --git a/lisp/subr.el b/lisp/subr.el
index 0d7bffb35f3..0b47da884b7 100644
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -2045,7 +2045,7 @@ Uses the `derived-mode-parent' property of the symbol to trace backwards."
 (put 'major-mode--suspended 'permanent-local t)
 
 (defun major-mode-suspend ()
-  "Exit current major, remembering it."
+  "Exit current major mode, remembering it."
   (let* ((prev-major-mode (or major-mode--suspended
                               (unless (eq major-mode 'fundamental-mode)
                                 major-mode))))
diff --git a/lisp/term/w32-win.el b/lisp/term/w32-win.el
index 198182fca72..e2c019fc548 100644
--- a/lisp/term/w32-win.el
+++ b/lisp/term/w32-win.el
@@ -485,6 +485,136 @@ numbers, and the build number."
 That includes all Windows systems except for 9X/Me."
   (getenv "SystemRoot"))
 
+;; The value of the following variable was calculated using the table in
+;; https://docs.microsoft.com/windows/desktop/Intl/unicode-subset-bitfields,
+;; by looking for Unicode subranges for which no USB bits are defined.
+(defconst w32-no-usb-subranges
+  '((#x000800 . #x0008ff)
+    (#x0018b0 . #x0018ff)
+    (#x001a20 . #x001aff)
+    (#x001bc0 . #x001bff)
+    (#x001c80 . #x001cff)
+    (#x002fe0 . #x002fef)
+    (#x00a4d0 . #x00a4ff)
+    (#x00a6a0 . #x00a6ff)
+    (#x00a830 . #x00a83f)
+    (#x00a8e0 . #x00a8ff)
+    (#x00a960 . #x00a9ff)
+    (#x00aa60 . #x00abff)
+    (#x00d7b0 . #x00d7ff)
+    (#x010200 . #x01027f)
+    (#x0102e0 . #x0102ff)
+    (#x010350 . #x01037f)
+    (#x0103e0 . #x0103ff)
+    (#x0104b0 . #x0107ff)
+    (#x010840 . #x0108ff)
+    (#x010940 . #x0109ff)
+    (#x010a60 . #x011fff)
+    (#x012480 . #x01cfff)
+    (#x01d250 . #x01d2ff)
+    (#x01d380 . #x01d3ff)
+    (#x01d800 . #x01efff)
+    (#x01f0a0 . #x01ffff)
+    (#x02a6e0 . #x02f7ff)
+    (#x02fa20 . #x0dffff)
+    (#x0e0080 . #x0e00ff)
+    (#x0e01f0 . #x0fefff))
+  "List of Unicode subranges whose support cannot be announced by a font.
+The FONTSIGNATURE structure reported by MS-Windows for a font
+includes 123 Unicode Subset bits (USBs) to identify subranges of
+the Unicode codepoint space supported by the font.  Since the
+number of bits is fixed, not every Unicode block can have a
+corresponding USB bit; fonts that support characters from blocks
+that have no USBs cannot communicate their support to Emacs,
+unless the font is opened and physically tested for glyphs for
+characters from these blocks.")
+
+(defun w32--filter-USB-scripts ()
+  "Filter USB scripts out of `script-representative-chars'."
+  (let (val)
+    (dolist (elt script-representative-chars)
+      (let ((subranges w32-no-usb-subranges)
+            (chars (cdr elt))
+            ch found subrange)
+        (while (and (consp chars) (not found))
+          (setq ch (car chars)
+                chars (cdr chars))
+          (while (and (consp subranges) (not found))
+            (setq subrange (car subranges)
+                  subranges (cdr subranges))
+            (when (and (>= ch (car subrange)) (<= ch (cdr subrange)))
+              (setq found t)
+              (push elt val))))))
+    (nreverse val)))
+
+(defvar w32-non-USB-fonts nil
+  "Alist of script symbols and corresponding fonts.
+Each element of the alist has the form (SCRIPT FONTS...), where
+SCRIPT is a symbol of a script and FONTS are one or more fonts installed
+on the system that can display SCRIPT's characters.  FONTS are
+specified as symbols.
+Only scripts that have no corresponding Unicode Subset Bits (USBs) can
+be found in this alist.
+This alist is used by w32font.c when it looks for fonts that can display
+characters from scripts for which no USBs are defined.")
+
+(defun w32-find-non-USB-fonts (&optional frame size)
+  "Compute the value of `w32-non-USB-fonts' for specified SIZE and FRAME.
+FRAME defaults to the selected frame.
+SIZE is the required font size and defaults to the nominal size of the
+default font on FRAME, or its best approximation."
+  (let* ((inhibit-compacting-font-caches t)
+         (all-fonts
+          (delete-dups
+           (x-list-fonts "-*-*-medium-r-normal-*-*-*-*-*-*-iso10646-1"
+                         'default frame)))
+         val)
+    (mapc (function
+           (lambda (script-desc)
+             (let* ((script (car script-desc))
+                    (script-chars (vconcat (cdr script-desc)))
+                    (nchars (length script-chars))
+                    (fntlist all-fonts)
+                    (entry (list script))
+                    fspec ffont font-obj glyphs idx)
+               ;; For each font in FNTLIST, determine whether it
+               ;; supports the representative character(s) of any
+               ;; scripts that have no USBs defined for it.
+               (dolist (fnt fntlist)
+                 (setq fspec (ignore-errors (font-spec :name fnt)))
+                 (if fspec
+                     (setq ffont (find-font fspec frame)))
+                 (when ffont
+                   (setq font-obj
+                         (open-font ffont size frame))
+                   ;; Ignore fonts for which open-font returns nil:
+                   ;; they are buggy fonts that we cannot use anyway.
+                   (setq glyphs
+                         (if font-obj
+                             (font-get-glyphs font-obj
+                                              0 nchars script-chars)
+                           '[nil]))
+                   ;; Does this font support ALL of the script's
+                   ;; representative characters?
+                   (setq idx 0)
+                   (while (and (< idx nchars) (not (null (aref glyphs idx))))
+                     (setq idx (1+ idx)))
+                   (if (= idx nchars)
+                       ;; It does; add this font to the script's entry in alist.
+                       (let ((font-family (font-get font-obj :family)))
+                         ;; Unifont is an ugly font, and it is already
+                         ;; present in the default fontset.
+                         (unless (string= (downcase (symbol-name font-family))
+                                          "unifont")
+                           (push font-family entry))))))
+                 (if (> (length entry) 1)
+                     (push (nreverse entry) val)))))
+          (w32--filter-USB-scripts))
+    ;; We've opened a lot of fonts, so clear the font caches to free
+    ;; some memory.
+    (clear-font-cache)
+    (and val (setq w32-non-USB-fonts val))))
+
 (provide 'w32-win)
 (provide 'term/w32-win)
 
diff --git a/lisp/textmodes/table.el b/lisp/textmodes/table.el
index 1f185e0f216..f684f4e4ca9 100644
--- a/lisp/textmodes/table.el
+++ b/lisp/textmodes/table.el
@@ -567,10 +567,6 @@
 ;; Consider the use of `:box' face attribute under Emacs 21
 ;; Consider the use of `modification-hooks' text property instead of
 ;; rebinding the keymap
-;; Maybe provide complete XEmacs support in the future however the
-;; "extent" is the single largest obstacle lying ahead, read the
-;; document in Emacs info.
-;; (progn (require 'info) (Info-find-node "elisp" "Not Intervals"))
 ;;
 ;;
 ;; ---------------
diff --git a/lisp/tooltip.el b/lisp/tooltip.el
index b1c69ae7368..eac510ba7ba 100644
--- a/lisp/tooltip.el
+++ b/lisp/tooltip.el
@@ -365,7 +365,10 @@ It is also called if Tooltip mode is on, for text-only displays."
       (let ((message-log-max nil))
         (message "%s" tooltip-previous-message)
         (setq tooltip-previous-message nil)))
-     (t
+     ;; Only stop displaying the message when the current message is our own.
+     ;; This has the advantage of not clearing the echo area when
+     ;; running after an error message was displayed (Bug#3192).
+     ((equal-including-properties tooltip-help-message (current-message))
       (message nil)))))
 
 (defun tooltip-show-help (msg)
diff --git a/lisp/vc/vc-cvs.el b/lisp/vc/vc-cvs.el
index d84700fc176..a9e79d7956c 100644
--- a/lisp/vc/vc-cvs.el
+++ b/lisp/vc/vc-cvs.el
@@ -440,7 +440,7 @@ REV is the revision to check out."
     (if vc-cvs-use-edit
         (vc-cvs-command nil 0 file "unedit")
       ;; Make the file read-only by switching off all w-bits
-      (set-file-modes file (logand (file-modes file) 3950)))))
+      (set-file-modes file (logand (file-modes file) #o7555)))))
 
 (defun vc-cvs-merge-file (file)
   "Accept a file merge request, prompting for revisions."
diff --git a/lisp/vc/vc-dir.el b/lisp/vc/vc-dir.el
index 9a6f6bb6874..e2259785923 100644
--- a/lisp/vc/vc-dir.el
+++ b/lisp/vc/vc-dir.el
@@ -864,10 +864,18 @@ with the command \\[tags-loop-continue]."
    delimited)
   (fileloop-continue))
 
-(defun vc-dir-ignore ()
-  "Ignore the current file."
-  (interactive)
-  (vc-ignore (vc-dir-current-file)))
+(defun vc-dir-ignore (&optional arg)
+  "Ignore the current file.
+If a prefix argument is given, ignore all marked files."
+  (interactive "P")
+  (if arg
+      (ewoc-map
+       (lambda (filearg)
+         (when (vc-dir-fileinfo->marked filearg)
+           (vc-ignore (vc-dir-fileinfo->name filearg))
+           t))
+       vc-ewoc)
+    (vc-ignore (vc-dir-current-file))))
 
 (defun vc-dir-current-file ()
   (let ((node (ewoc-locate vc-ewoc)))
diff --git a/lisp/vc/vc-svn.el b/lisp/vc/vc-svn.el
index 3c50c8fff64..88a280d10f3 100644
--- a/lisp/vc/vc-svn.el
+++ b/lisp/vc/vc-svn.el
@@ -366,8 +366,9 @@ FILE is a file wildcard, relative to the root directory of DIRECTORY."
 (defun vc-svn-ignore-completion-table (directory)
   "Return the list of ignored files in DIRECTORY."
   (with-temp-buffer
-    (vc-svn-command t t nil "propget" "svn:ignore" (expand-file-name directory))
-    (split-string (buffer-string))))
+    (when (zerop (vc-svn-command
+                  t t nil "propget" "svn:ignore" (expand-file-name directory)))
+      (split-string (buffer-string) "\n"))))
 
 (defun vc-svn-find-admin-dir (file)
   "Return the administrative directory of FILE."
diff --git a/lisp/vc/vc.el b/lisp/vc/vc.el
index 4cac1539289..c982b0220e3 100644
--- a/lisp/vc/vc.el
+++ b/lisp/vc/vc.el
@@ -1417,17 +1417,22 @@ remove from the list of ignored files."
 
 (defun vc-default-ignore (backend file &optional directory remove)
   "Ignore FILE under the VCS of DIRECTORY (default is `default-directory').
-FILE is a file wildcard, relative to the root directory of DIRECTORY.
+FILE is a wildcard specification, either relative to
+DIRECTORY or absolute.
 When called from Lisp code, if DIRECTORY is non-nil, the
 repository to use will be deduced by DIRECTORY; if REMOVE is
 non-nil, remove FILE from ignored files.
 Argument BACKEND is the backend you are using."
   (let ((ignore
          (vc-call-backend backend 'find-ignore-file (or directory default-directory)))
-        (pattern (file-relative-name
-                  (expand-file-name file) (file-name-directory file))))
+        file-path root-dir pattern)
+    (setq file-path (expand-file-name file directory))
+    (setq root-dir (file-name-directory ignore))
+    (when (not (string= (substring file-path 0 (length root-dir)) root-dir))
+      (error "Ignore spec %s is not below project root %s" file-path root-dir))
+    (setq pattern (substring file-path (length root-dir)))
     (if remove
-        (vc--remove-regexp pattern ignore)
+        (vc--remove-regexp (concat "^" (regexp-quote pattern ) "\\(\n\\|$\\)") ignore)
       (vc--add-line pattern ignore))))
 
 (defun vc-default-ignore-completion-table (backend file)
diff --git a/lisp/wid-browse.el b/lisp/wid-browse.el
index dbc41009c77..3124a9c01e5 100644
--- a/lisp/wid-browse.el
+++ b/lisp/wid-browse.el
@@ -89,7 +89,11 @@ if that value is non-nil."
 (defun widget-browse-at (pos)
   "Browse the widget under point."
   (interactive "d")
-  (let* ((field (get-char-property pos 'field))
+  (let* ((field (or
+                 ;; See comments in `widget-specify-field' to know why we
+                 ;; need this.
+                 (get-char-property pos 'real-field)
+                 (get-char-property pos 'field)))
          (button (get-char-property pos 'button))
          (doc (get-char-property pos 'widget-doc))
          (text (cond (field "This is an editable text area.")
diff --git a/lisp/wid-edit.el b/lisp/wid-edit.el
index 9bc7a076eec..7ed7b81280b 100644
--- a/lisp/wid-edit.el
+++ b/lisp/wid-edit.el
@@ -414,6 +414,7 @@ the :notify function can't know the new value.")
 
 (defmacro widget-specify-insert (&rest form)
   "Execute FORM without inheriting any text properties."
+   (declare (debug body))
   `(save-restriction
     (let ((inhibit-read-only t)
           (inhibit-modification-hooks t))