Bug 439815

Created attachment 140035 [details]
ghost window

I haven't encountered the bug for a while after I update to git version of KDE. Perhaps they have fixed the bug.

Happens to me somewhat often, once every few days, I have to restart kwin to get it to work again


Operating System: arch
KDE Plasma Version: 5.22.3
KDE Frameworks Version: 5.84.0
Qt Version: 5.15.2
Kernel Version: 5.12.15-arch1-1 (64-bit)
Graphics Platform: X11
Processors: 16 × AMD Ryzen 7 3700X 8-Core Processor
Memory: 31.3 GiB of RAM
Graphics Processor: NVIDIA GeForce RTX 2070 SUPER/PCIe/SSE2

When this bug happens the next time, can you please open the terminal, run the following command `qdbus org.kde.KWin /KWin supportInformation`, and post its output here?

Created attachment 140240 [details]
output from supportInformation

Here's 2 outputs, one from when the window is ghosted but still open

The next output is from after closing the ghosted window and it leaves an imprint in the background

Created attachment 140242 [details]
supportInformation output

Are you using virtual desktops? Reminds me of Bug 438552.

I'm not using virtual desktops - system with two monitors (laptop built in + external).

#438552 says they can't focus but in this case, I can focus and use the window normally. It's just transparent and then leaves a ghost image when I close it.

(In reply to Nate Graham from comment #7)
> Are you using virtual desktops? Reminds me of Bug 438552.

Yes, it appears like the translucency effect also causes this bug.

`kwin --replace` also fixes this issue when it happens.

(In reply to Devin Zuczek from comment #8)
> I'm not using virtual desktops - system with two monitors (laptop built in +
> external).
> 
> #438552 says they can't focus but in this case, I can focus and use the
> window normally. It's just transparent and then leaves a ghost image when I
> close it.

Yup this is exactly the behavior I'm coming across. I'll send my own logs once I see it happen again. Admittedly it does seem to happen less often since I reset to defaults+wobbly windows, but it does still happen.

(In reply to Nate Graham from comment #7)
> Are you using virtual desktops? Reminds me of Bug 438552.

Oops, I meant to reply to that other bug... I think it might be a duplicate? Both sound like the behavior I'm seeing. In the second comment in that other bug they said they didn't need to switch desktops to trigger the bug.

*** Bug 442114 has been marked as a duplicate of this bug. ***

For me running: kwin --replace

indeed removes the ghost/dead windows, but leaves the desktop in a near unusable state, where its working but everything is running very very very slowly, eg typing into a konsole windows lags multiple seconds and window operations drag like a 1980's computer.

the only "fix" that works for me is to restart the window manager entirely, ie log out and log back in.

I can support the observation that MarkH made:

I am on Fedora 34, KDE installed from the Fedora repositories (Plasma v5.22.5, KDE frameworks v5.85.0, Qt 5.15.2). I regularly get the same transparent window effect. Restarting kwin fixes this, but afterwards everything is unusably slow.

Disabling the translucency effect also fixes ghosted windows, without the kwin --replace downside.

Top tip from Phil O, just toggle translucency off and on again clears all the "hung" windows.

I've been having this problem for a while and have been doing a kwin_x11 --replace to fix it. More interesting is that on a new install on a laptop with different hardware on a blank install (same versions as below), I experience the same problem.


Operating System: Arch Linux
KDE Plasma Version: 5.22.5
KDE Frameworks Version: 5.86.0
Qt Version: 5.15.2
Kernel Version: 5.14.6-arch1-1 (64-bit)
Graphics Platform: X11
Processors: 16 × AMD Ryzen 7 3700X 8-Core Processor
Memory: 31.3 GiB of RAM
Graphics Processor: NVIDIA GeForce RTX 2070 SUPER/PCIe/SSE2

Created attachment 142300 [details]
window with see through hole

I disabled translucency from system setting and I am still having these problem, see this issues already 3 time in a week. I though it went away, this time please see attached pic, "win-with-hole.png" the window has a hole and when I mode it around the "see through hole" doesn't go away!

Vlad's patch (https://codereview.qt-project.org/c/qt/qtdeclarative/+/376014) has been merged, so this is officially fixed in Qt. We'll see about backporting the fix to the KDE patch collection for Qt 5.15.

Seems https://bugs.kde.org/show_bug.cgi?id=438552 should be fixed by this as well Nate.

Ah yes, you're right! Thanks for catching that!

Qt backport request: https://invent.kde.org/qt/qt/qtdeclarative/-/merge_requests/8

*** Bug 443493 has been marked as a duplicate of this bug. ***

*** Bug 445840 has been marked as a duplicate of this bug. ***

*** Bug 457126 has been marked as a duplicate of this bug. ***

*** Bug 457103 has been marked as a duplicate of this bug. ***

Ghosts still remain sometimes in Plasma 6.1.5 when using translucency effect.

Operating System: Kubuntu 24.10
KDE Plasma Version: 6.1.5
KDE Frameworks Version: 6.6.0
Qt Version: 6.6.2
Kernel Version: 6.11.3-mve (64-bit)
Graphics Platform: Wayland
Processors: 8 × Intel® Core™ i7-10510U CPU @ 1.80GHz
Memory: 31.1 GiB of RAM
Graphics Processor: Mesa Intel® UHD Graphics
Manufacturer: Notebook
Product Name: N141CU

This is a fairly old bug report and the code has changed a lot since it was reported. There's a very good chance the issue you're experiencing is caused by something else, even if the outward symptoms look and feel the same. Can you please submit a new bug report? Thank you!