Hi @Andreas_Hegenberg I restart my machine every few days, and this has been happening for months now (only Slack and Firefox). I'll restart now and see if I can replicate the glitch.
Re: @Christian_Drewitz - I almost never drag windows, so the glitches I experience are all triggered by keyboard shortcuts.
Something else occurs to me - In the previous tests, I switched back and forth between BTT and BST, so restarting the apps didn't solve any issues... A quick search suggests that restarting Dock might assist in refreshing the resizing API: https://apple.stackexchange.com/questions/179330/windows-jump-around-when-resizing.
killall Dock didn't fix resizing Firefox for me just now
EDIT: hmm... reply limit reached in this thread
Restarting my computer didn't have any effect on the bug, but I do notice a pattern in the glitch...
- fullscreen always works when the window starts at left-half
- fullscreen always fails from half-right (window resizes to a narrow width, positioned centre or just left of centre)
- fullscreen to half-left always works
- fullscreen to half-right actually results in half-left, triggering half-right a second time works
The pattern being: I can toggle between any of these three states reliably as long as I transition through the half left state.
Hope that helps... Guess I'll try upgrading OSX sooner or later.
If there's more detailed diagnostic data you need, I can repro this sequence reliably...
EDIT: (Sorry... I'm only permitted to edit this item due to forum limits)
So, based on your advice, I've identified that https://timingapp.com/ is the culprit in my setup. I did a pretty comprehensive isolation test, starting with safe mode, but then ramping up to my usual configuration, and timing.app is the definitely to blame. If I start without Timing, then Firefox and Slack snap fine left, right, max, between monitors; as soon as I start Timing, I get the behaviour exhibited above. If I quit Timing (and, most importantly their Menubar app), then restart Firefox, snapping functions reliably.
BTW, I purchased Magnet, and have can reproduce exactly the same behaviour in that app!
@Andreas_Hegenberg - do you have any advice for other app developers on how to avoid glitching window snapping? I'd really rather not sacrifice time tracking!
I reported the bug, linking to this thread, and the dev replied:
I was able to reproduce the issue; you can avoid it by disabling “Advanced Accessibility tracking” in the Timing preferences (see the attached screenshot). Note that this will cause Timing to no longer be able to track Firefox URLs and individual Slack channels in some cases.
Issue solved, tx for reading