Bug 504293

Summary:	Hidden Electron windows take a very long time to show again, but icon appears instantly
Product:	[Plasma] kwin	Reporter:	kderemie
Component:	compositing	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED UNMAINTAINED
Severity:	normal	CC:	nate
Priority:	NOR
Version First Reported In:	5.27.12
Target Milestone:	---
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description kderemie 2025-05-15 20:26:43 UTC

SUMMARY
Hidden Electron windows take a very long time to show again, but icon appears instantly.

STEPS TO REPRODUCE
1. See this issue and the attached repro Gist URL
2. Run that repro Gist in Electron Fiddle (https://www.electronjs.org/fiddle)

OBSERVED RESULT
Taskbar icon appears instantly, but window takes several seconds to appear.

EXPECTED RESULT
Taskbar icon and window both appear instantly.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Kubuntu 24.04
KDE Plasma Version: 5.27.12
KDE Frameworks Version: 5.115.0
Qt Version: 5.15.13

ADDITIONAL INFORMATION
Since at least KDE 5.27.12, but only affecting Electron 34.0 and above.

Affects X11 and Wayland.

Disabling the compositor fully mitigates the issue, but is not viable with Wayland.

Comment 1 Nate Graham 2025-05-16 14:02:17 UTC

I'm afraid Plasma 5.27.12 is unfortunately no longer eligible for support or maintenance from KDE.

Plasma is a fast-moving project, and bugs in one version are often fixed in the next one. Please update to Plasma 6.3 as soon as your distro offers it to you; in this case, that means updating to Kubuntu 25.04. If you need support for Plasma 5.27, please contact the Kubuntu folks, who bear the responsibility of providing support for older releases.

If this issue is still reproducible in Plasma 6.3, feel free to re-open this bug report.

Thanks for understanding!