bug#54326: 29.0.50; Bug with display-buffers-alist

[martin rudalics]

> Make an init.el just containing the lines
>
> (setq
>   display-buffer-base-action
>     '((display-buffer-reuse-window display-buffer-pop-up-frame)
>      (reusable-frames . t))
>   display-buffer-alist
>       '(("\\`\\*info\\*\\'"
>        (display-buffer-reuse-window display-buffer-pop-up-frame)
>         (dedicated . t)
>         (pop-up-frame-parameters
>         (tool-bar-lines . 1)
>         (width . 78)
>         (height . 52)
>         (left . 786)
>         (unsplittable)
>         (left-fringe . 8)
>         (right-fringe . 0)
>         (line-spacing . 0)
>         (font . "Menlo-15")
>         (top . 110)
>         ))
>      ("[.]"
>       (display-buffer-reuse-window display-buffer-pop-up-frame)
>         (dedicated . t)
>         (pop-up-frame-parameters
>         (tool-bar-lines . 1)
>         ;; (left . 0)
>         (left . 100)
>         (left-fringe . 8)
>         (right-fringe . 0)
>         (top . 0)
>         (height . 56)
>         (width . 87)
>         (font . "SF Mono-18")
>         (line-spacing . 5)
>        ))
> ))
>
> Start Emacs.app. Open a file, say foo.tex. From the buffer showing
> foo.tex, do Menu>Help>"Read the Emacs Manual". The latter action makes the
> toolbar-buttons over foo.tex to disappear. Only after going back to
> foo.tex _and_ there doing M_x, it shows up again. But then the
> toolbar-buttons over "Read the Emacs Manual" disappear.

AFAICT this is in not related to 'display-buffer-alist' but very likely
Mac-specific, caused by the fact that you use different fonts for Info
and the other buffer.  Can you please try with emacs -Q where you first
evaluate

(set-frame-parameter nil 'font "SF Mono-18")

and then do C-x 5 2, M-x info and evaluate

(set-frame-parameter nil 'font "Menlo-15")

in the second frame.

martin