Subject: bug#79323: 30.2; Control-X-prefix not remapable

From: Juri Linkov <[email-masked]>
Date: Thu, 28 Aug 2025 22:13:30 +0300

> Probably there is no way to do this with 'defvar-keymap'?
> This leaves only one solution with
>
>   (define-key ctl-x-map ...

I meant this patch:

diff --git a/lisp/tab-line.el b/lisp/tab-line.el
index 7caae8bc2c1..b1f097effd4 100644
--- a/lisp/tab-line.el
+++ b/lisp/tab-line.el
@@ -1277,14 +1277,12 @@ tab-line-event-start
-(defvar-keymap tab-line-mode-map
-  :doc "Keymap for keys of `tab-line-mode'."
-  "C-x <left>"    #'tab-line-switch-to-prev-tab
-  "C-x C-<left>"  #'tab-line-switch-to-prev-tab
-  "C-x M-<left>"  #'tab-line-move-tab-backward
-  "C-x <right>"   #'tab-line-switch-to-next-tab
-  "C-x C-<right>" #'tab-line-switch-to-next-tab
-  "C-x M-<right>" #'tab-line-move-tab-forward)
+(define-key ctl-x-map [left] #'tab-line-switch-to-prev-tab)
+(define-key ctl-x-map [C-left] #'tab-line-switch-to-prev-tab)
+(define-key ctl-x-map [M-left] #'tab-line-move-tab-backward)
+(define-key ctl-x-map [right] #'tab-line-switch-to-next-tab)
+(define-key ctl-x-map [C-right] #'tab-line-switch-to-next-tab)
+(define-key ctl-x-map [M-right] #'tab-line-move-tab-forward)

But this will throw away all user keys customized
in 'tab-line-mode-map' :-(