Subject: bug#78418: 31.0.50; Change in fit-frame-to-buffer doesn't work with transient-posframe

From: Gerd Möllmann <[email-masked]>
Date: Mon, 19 May 2025 12:45:10 +0200

martin rudalics <[email-masked]> writes:

>> Maybe we should set the default of frame-resize-pixelwise to true? Or at
>> least on macOS? IIRC you recommended setting it to true unless the WM
>> does mess with the frame size.
>
> As a rule WMs don't mess with frame sizes.  Today most WMs DTRT.
> Setting it to t means that people who expect their frames to always
> resize only by character increments will holler.
>
>> On macOS this seems to be the right
>> default.
>
> When on macOS with 'frame-resize-pixelwise' nil you drag a frame border
> with the mouse, does it resize by pixels or by character increments?

I think it resizes to character bounds with frame-resize-pixelwise nil,
and to pixels with it being t.

For transient-posframe child frames, when f-r-p is nil. things go wrong
because Posframe binds frame-resize-pixelwise to t, and transient uses
the default nil when fit-frame-to-buffer is called. That's what I showed
in the screen shot.