Bug 459976

Summary: Able to click on an application behind a maximized application
Product: [Plasma] kwin Reporter: hch12907 <haochengho12907>
Component: wayland-genericAssignee: KWin default assignee <kwin-bugs-null>
Status: RESOLVED FIXED    
Severity: normal CC: haochengho12907, nate
Priority: NOR    
Version First Reported In: 5.25.90   
Target Milestone: ---   
Platform: Arch Linux   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: Video showing the bug in action

Description hch12907 2022-10-04 15:26:17 UTC
Created attachment 152584 [details]
Video showing the bug in action

SUMMARY
See the title. It also noteworthy that this is only a problem when I disable the application's titlebar and frame (relying on the client-side decoration).

STEPS TO REPRODUCE
1. Maximize an application
2. Disable titlebar and frame for that application
3. Move the cursor to the very top of the screen
4. Click
5. Occasionally the application *behind* this maximized application will be clicked, and thus move to the front

OBSERVED RESULT
I am able to click on an application that is behind the maximized application.

It is easy to show this on Firefox, as the tab will not be highlighted when the mouse cursor is actually hovering over the window behind. The attached video shows this in action.

EXPECTED RESULT
I shouldn't be able to do that.

ADDITIONAL INFORMATION
This is done on a 1920x1080 display, with 125% scaling.
Comment 1 Nate Graham 2022-10-10 01:38:43 UTC
> 125% scaling.
Relevant information. I *think* this has been fixed for the final release; can you test again in a few days once it's out?
Comment 2 hch12907 2022-10-13 18:09:40 UTC
I cannot reproduce the bug after upgrading to 5.26. Marking this as resolved and thanks!