* doc/emacs/frames.texi (Tab Bars): Mention tab-bar-new-tab-to,
tab-bar-close-last-tab-choice, tab-bar-close-tab-select, tab-undo,
tab-select, tab-bar-history-mode.

* doc/emacs/windows.texi (Tab Line): Mention tab-line-tabs-function.

* lisp/tab-bar.el (tab-bar-select-tab-modifiers): Mention
tab-bar-tab-hints in docstring.
(tab-bar-tab-hints): Mention tab-bar-select-tab-modifiers
in docstring.
(tab-bar-select-tab): Mention tab-bar-select-tab-modifiers
in docstring.
(tab-bar-switch-to-tab): Expand the docstring.
(tab-bar-new-tab-to): Fix bug in handling 'left' value.
(tab-bar-close-tab): Fix bug in handling 'left' value.
(tab-bar-undo-close-tab): Use funcall tab-bar-tabs-function
instead of direct call to tab-bar-tabs.
(tab-bar-history-back, tab-bar-history-forward): Add docstrings.
(tab-bar-history-mode): Expand docstring.

* lisp/tab-line.el (tab-line-format): Fix bug for handling window
switching that should set face 'tab-line-tab-current'.

* lisp/tab-line.el (tab-line-format-template): Use tab-line-new-button-show.
(tab-line-new-tab-choice): Remove choice 'nil' with "No button".
(tab-line-separator): Add docstring.

* lisp/tab-line.el (tab-line-format): Use buffer-name in the cache key
instead of just buffer object to invalidate the cache on buffer renaming.
(tab-line-format-template): Always leave the separator after the last tab
like tab-bar.el already does.

Distinguish offsets between manual-vs-automatic scrolling
as integers-vs-floats instead of positive-vs-negative integers.

* lisp/tab-line.el (tab-line-format-template): Use 'numberp'
instead of 'integerp', and 'truncate' instead of 'abs'.
(tab-line-format): When the window-buffer was updated, set window-parameter
to float to enable auto-hscroll after it was disabled on manual scrolling.
(tab-line-auto-hscroll-buffer): New variable with internal buffer.
(tab-line-auto-hscroll): Erase in tab-line-auto-hscroll-buffer.
Use 'numberp' instead of 'integerp', 'truncate' instead of 'abs',
and 'float' instead of '-'.
(tab-line-hscroll): Use 'numberp' instead of 'integerp',
and 'truncate' instead of 'abs'.

* lisp/tab-bar.el (tab-bar) <defface>:
* lisp/tab-line.el (tab-line) <defface>:
Check for min-colors 88 instead of type x.

* lisp/tab-bar.el (tab-bar-tab-name-ellipsis): Use shorter name
instead of tab-bar-tab-name-truncated-ellipsis.
(tab-bar-new-tab-to) <defcustom>: Add 'function' option.
(tab-bar-new-tab-to) <function>: Use it.

* lisp/tab-line.el (tab-line-close-tab): Add missing arg 'tab' to
tab-line-close-tab-function funcall.

* lisp/tab-line.el (tab-line-tab-name-truncated-max): New defcustom.
(tab-line-tab-name-truncated-buffer): Use tab-line-tab-name-truncated-max
consistently with similar options in tab-bar.el.
(tab-line-tabs-limit): Remove variable.
(tab-line-tabs-window-buffers): Remove use of tab-line-tabs-limit
that was an experimental feature before horizontal scrolling was implemented.
(tab-line-close-tab-function): Rename from tab-line-close-tab-action
and allow a customizaed function as option.
(tab-line-close-tab): Call function if tab-line-close-tab-function
is customized to a function.

* lisp/tab-bar.el (tab-bar-tab-name-function): Add option
tab-bar-tab-name-truncated.
(tab-bar-tab-name-truncated-max): New defcustom.
(tab-bar-tab-name-truncated-ellipsis): New variable.
(tab-bar-tab-name-truncated): New function.

Check for nil value returned by previous-single-property-change that
happens when tab name is longer than window width.

* src/term.c (handle_one_term_event): Call tty_handle_tab_bar_click.

* src/xdisp.c (tty_handle_tab_bar_click): Force reset of up_modifier bit
from the event modifiers.

* lisp/tab-line.el (tab-line-tab-current): No need to use inverse-video
on console/xterm because the selected tab already uses inverse-video.

Run "TZ=UTC0 admin/update-copyright $(git ls-files)".