Bug 478909

Summary:	Resizing snapped windows does not work when window touches a panel
Product:	[Plasma] kwin	Reporter:	Jakob Petsovits <jpetso>
Component:	Quick Tiling	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	CONFIRMED ---
Severity:	minor	CC:	nate
Priority:	NOR	Keywords:	usability
Version First Reported In:	5.27.9
Target Milestone:	---
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Jakob Petsovits 2023-12-23 01:43:30 UTC

SUMMARY
A window that gets resized taller to touch my bottom panel can not be decreased in height after letting go of the mouse press. Probably the same as Bug 429571 but I don't know if there's any difference between quick-tiled windows and regularly resized windows in that respect, so I'll open a new bug.


STEPS TO REPRODUCE
1. Take any small window that's less tall than the current desktop.
2. Drag the bottom resize handle right down to the edge of a bottom panel, to make it snap.
3. Drop the handle, let go of your mouse/touchpad press.
4. Try grabbing the bottom window edge again to make it smaller, because you've changed your mind about the height.

OBSERVED RESULT
There's nowhere you can grab the bottom window edge now. If you're lucky, maybe you have a few pixels around the window corners where you get a diagonal resize handle. That's not good enough for decent usability.

EXPECTED RESULT
I can pick up the bottom resize handle where I dropped it.

SOFTWARE/OS VERSIONS
Operating System: Arch Linux 
KDE Plasma Version: 5.27.9
KDE Frameworks Version: 5.112.0
Qt Version: 5.15.11
Kernel Version: 6.6.3-arch1-1 (64-bit)
Graphics Platform: X11
Processors: 8 × Intel® Core™ i7-8565U CPU @ 1.80GHz
Memory: 15.3 GiB of RAM
Graphics Processor: Mesa Intel® UHD Graphics 620

ADDITIONAL INFORMATION
Same issue both on X11 and Wayland.

Comment 1 Jakob Petsovits 2023-12-23 01:48:15 UTC

The issue is still present in my very latest Plasma 6 Beta 2 (or about 2 days newer) self-built session, but I booted into the wrong X11 session for unrelated reasons so that's what it got filed under.

Comment 2 Nate Graham 2024-02-16 00:12:13 UTC

Right, without KWin-added window borders taking up their own space, there are no pixels for the cursor to turn into a resize cursor without taking some space away from either the window or the panel. Not sure if this is really fixable. I guess in principle we could make it as good (or bad) as it is when a non-snapped.tiled window touches the panel, which is to say it gets a one pixel drag-resize area. That's pretty bad, but I guess it's better than nothing.