Fix documentation of 'normal-mode' in buffers that don't visit files

* lisp/files.el (normal-mode):
* lisp/subr.el (run-mode-hooks):
* doc/emacs/modes.texi (Choosing Modes): Mention the caveat with
'normal-mode' in buffers not visiting files.  (Bug#61925)
* lisp/files.el (hack-local-variables): Doc fix.

1 files changed, 6 insertions, 3 deletions

diff --git a/doc/emacs/modes.texi b/doc/emacs/modes.texi
index 0e4b15fb514..d2f96af0b55 100644
--- a/doc/emacs/modes.texi
+++ b/doc/emacs/modes.texi
@@ -473,9 +473,12 @@ specify which mode you prefer.
   If you have changed the major mode of a buffer, you can return to
 the major mode Emacs would have chosen automatically, by typing
 @kbd{M-x normal-mode}.  This is the same function that
-@code{find-file} calls to choose the major mode.  It also processes
-the file's @samp{-*-} line or local variables list (if any).
-@xref{File Variables}.
+@code{find-file} calls to choose the major mode.  If the buffer is
+visiting a file, this command also processes the file's @samp{-*-}
+line and file-local variables list (if any).  @xref{File Variables}.
+If the buffer doesn't visit a file, the command processes only the
+major mode specification, if any, in the @samp{-*-} line and in the
+file-local variables list.
 
 @vindex change-major-mode-with-file-name
   The commands @kbd{C-x C-w} and @code{set-visited-file-name} change to