Bug 444334

Summary: Mouse Mark effect draws arrows if ctrl modifier pressed
Product: [Plasma] kwin Reporter: Andrew Shark <ashark>
Component: effects-variousAssignee: KWin default assignee <kwin-bugs-null>
Status: RESOLVED FIXED    
Severity: normal CC: hsantanna, nate
Priority: NOR    
Version First Reported In: unspecified   
Target Milestone: ---   
Platform: Other   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: Mouse mark arrows

Description Andrew Shark 2021-10-24 17:05:03 UTC
Created attachment 142829 [details]
Mouse mark arrows

Mouse Mark effect has shortcut Shift + Meta. It works as expected (draws line after mouse) if the only these modifiers are held. But if you additionally  press Ctrl (i.e. hold Ctrl + Shift + Meta), then the effect start drawing arrows. See the attached video.
If moving mouse rather slow, the arrows' length is short and they may look like just angles.

STEPS TO REPRODUCE
1. Activate Mouse Mark effect in System Settings.
2. Press and hold Ctrl + Shift + Meta and move your mouse.

OBSERVED RESULT
Mouse Mark draws arrows following mouse position.

EXPECTED RESULT
It should not draw arrows. Effect should not draw anything when additional modifier (ctrl) is pressed.

SOFTWARE/OS VERSIONS
Operating System: Arch Linux
KDE Plasma Version: 5.23.1
KDE Frameworks Version: 5.87.0
Qt Version: 5.15.2
Kernel Version: 5.14.12-arch1-1 (64-bit)
Graphics Platform: X11

ADDITIONAL INFORMATION
When pressing Meta+Shift+Alt, the effect is not drawing anything, as expected.
Comment 1 Nate Graham 2021-10-25 21:20:36 UTC
Can reproduce, though I can't tell whether this is a bug, or a hidden feature. It feels a bit too rough to be a feature, though to be fair that's common for a lot of old effects.
Comment 2 Henrique Sant'Anna 2022-10-06 14:57:54 UTC
It's a feature.

Press Ctrl + Shift + Meta, move the mouse pointer, press Ctrl + Shift + Meta again. Only works on Wayland.

Probably it would be better to require a mouse down-up do draw the arrow, not only the keyboard short-keys.
Comment 3 Andrew Shark 2022-11-17 17:11:45 UTC
What is the purpose of that "feature"?