Alex <agrambot@gmail.com> writes:

> The menus that display when clicking on various items in the mode line
> (major mode, minor mode, buffer position) don't display correctly with
> certain monitor setups on X, specifically when using multiple monitors
> where the bottoms of the monitors are not even. They appear squished and
> are effectively unusable.
>
> FWIW, a similar issue appeared with the mode line tooltips that
> displayed when hovering over these items in Emacs 24.5, but they have
> since been fixed.
>
> The menu bar menus do not suffer this problem.
>
> When running from the command line, the following message usually
> appears:
>
> *** BUG ***
> In pixman_region32_init_rect: Invalid rectangle passed
> Set a breakpoint on '_pixman_log_error' to debug
>
> I tried to debug this in gdb, but setting the breakpoint made X hang
> when encountering this issue, so I was unable to procure a backtrace.
>
> I have attached a picture showing the problem. The static displayed is
> the area that I am unable to see, but is included by scrot. The squished
> prompt was from clicking on `Lisp Interaction' in the mode line.

This is still an issue in current master.

The tooltip issue I mentioned above last year was fixed in 7b14da444, so
I tried using pretty much the same code to fix this issue; a proof of
concept diff is included below.

I don't know if it's a good approach though. Partially because I have no
idea why the values of req.{height, width} are so large, why they differ
in different Emacs sessions, and how they relate to the other
width/height variables.

In any case, perhaps this functionality should be abstracted into a
procedure that just computes the dimensions of the current monitor?