Bug 484394

Summary: Dragging tabs from Firefox on to the Desktop is inaccurate and unreliable
Product: [Plasma] kwin Reporter: DeKay <darrylkacher>
Component: wayland-genericAssignee: KWin default assignee <kwin-bugs-null>
Status: RESOLVED UPSTREAM    
Severity: normal CC: mobile.harvey, spleefer90, xaver.hugl
Priority: NOR    
Version: 6.0.2   
Target Milestone: ---   
Platform: Arch Linux   
OS: Linux   
Latest Commit: Version Fixed In:
Sentry Crash Report:
Attachments: Screencast showing drag & drop of Firefox tabs to various sides of window

Description DeKay 2024-03-24 16:37:05 UTC 
Created attachment 167707 [details]
Screencast showing drag & drop of Firefox tabs to various sides of window

SUMMARY
I am running Firefox on KDE 6.0.2  under Wayland. If I drag a Firefox tab above the current Firefox window, it usually doesn't work (the drop is rejected). But if I drag a tab to the left of the current window, or the right, or below, or inside, the drop always works. However, even when it does work, I would expect the window to open in the vicinity of the drop. It doesn't do that either.

See attached screencast.  It starts by multiple attempts to drop a tab above the current window that don't work. Other drops to the left, right, bottom, and inside of the current window always work. However, those that work always appear to the left of the current window even though there was space on the other edges.

I found in generating this screencast that a drag above the current window will sometimes work but only if it was preceded by drags to the other sides of the current window first. The bug can most reliably be reproduced by starting with a drop above the current window.

STEPS TO REPRODUCE
1. Create one Firefox window with a number of tabs
2. Starting with a drag above the current window, drop tabs above, below, left, and right of the current window

OBSERVED RESULT
Tabs dropped above the  window won't drop. The other will.

EXPECTED RESULT
Drops should work regardless of where they are relative to the current window and should appear in the general location of the drop.

SOFTWARE/OS VERSIONS
Linux Kernel: 6.8.1
KDE Plasma Version: 6.0.2 running under Wayland
KDE Frameworks Version: 24.02.0
Qt Version: 6.6.2.4
Firefox Version 124.0

ADDITIONAL INFORMATION
I think this is the same bug I described in https://bugs.kde.org/show_bug.cgi?id=473212 that was closed by David Edmundson as "This works on latest firefox with kwin master (at time of writing)". I am guessing that it only worked for him because he might not have been dragging above the window. I didn't realize at the time that this bug only happened in that case.

I haven't tried this under xwindows to see what it does.
Comment 1 Nick 2024-03-31 10:46:20 UTC 
I can duplicate this as per the screencast on Neon / Intel graphics. On Wayland dragging the tab off the top of of the window generally never works. On X11 it also does not work UNLESS you drag the tab up enough so the preview thumbnail fully clears the top of the Firefox window. 

Marking this as confirmed for further review.
Comment 2 DeKay 2024-03-31 14:27:25 UTC 
(In reply to Nick from comment #1)
> I can duplicate this as per the screencast on Neon / Intel graphics. On
> Wayland dragging the tab off the top of of the window generally never works.
> On X11 it also does not work UNLESS you drag the tab up enough so the
> preview thumbnail fully clears the top of the Firefox window. 
> 
> Marking this as confirmed for further review.

Thanks for confirming this. I can also confirm your observations on the X11 side: the thumbnail needs to clear the top of the window for the drop to work.  I should have mentioned that in my original report but forgot.
Comment 3 Martin 2024-04-12 08:02:20 UTC 
Possible duplicate of https://bugs.kde.org/show_bug.cgi?id=484336
Comment 4 Zamundaaa 2024-04-12 19:37:18 UTC 
To fix this, Firefox has to support the xdg toplevel drag protocol. There's nothing we can do about it, please report this to Mozilla.