bug#20265: 24.5; Corrupted mode-line with :box attribute set

[Alan Third]

Nick Helm <nick@tenpoint.co.nz> writes:

> ;; Start emacs in a new GUI frame with
> ;; /Applications/Emacs.app/Contents/MacOS/Emacs -Q
>
> ;; In *scratch* use C-x C-e to set the mode-line face :box
> ;; attribute to something ridiculous but easy to see.
>
> (set-face-attribute 'mode-line nil :box '(:line-width 15))
>
> ;; Notice the obscured coding system flag in the mode-line. Mouse
> ;; over the mode-line and observe the mode-line status flags become
> ;; visually corrupted.
>
> ;; Further, turn off the mode-line's 3D effects by setting :box 
> ;; atttributes.
>
> (set-face-attribute 'mode-line nil :box nil)
>
> (set-face-attribute 'mode-line-highlight nil :box nil)
>
> ;; Mouse over the mode-line and observe the unexpected
> ;; mode-line-highlight face.
>
> ;; Note that this is reproducible in 24.4.

I believe this was fixed in Emacs 26 against bug#23755.

-- 
Alan Third