Bug 422202

Summary: Blur region for GTK3 apps is bigger than it should
Product: [Plasma] kwin Reporter: Azarilh <azarilh>
Component: compositingAssignee: KWin default assignee <kwin-bugs-null>
Status: RESOLVED FIXED    
Severity: normal CC: nate, sk.griffinix
Priority: NOR Flags: vlad.zahorodnii: ReviewRequest+
Version: 5.18.5   
Target Milestone: ---   
Platform: Kubuntu   
OS: Linux   
URL: https://invent.kde.org/plasma/kwin/-/merge_requests/32
Latest Commit: Version Fixed In: 5.19.0
Sentry Crash Report:
Attachments: See the blur effect outside the windows' regions

Description Azarilh 2020-05-29 00:48:28 UTC
Created attachment 128893 [details]
See the blur effect outside the windows' regions

The blur effect under the windows have a bigger region than what they should. It's really ugly and annoying. It happens with GTK3 apps only, like Firefox. I'm not sure what other information should i add, to be honest. Just look at the screenshot to understand.

Operating System: Kubuntu 20.04
KDE Plasma Version: 5.18.5
KDE Frameworks Version: 5.68.0
Qt Version: 5.12.8
Kernel Version: 5.4.0-31-generic
OS Type: 64-bit
Comment 1 Azarilh 2020-05-29 03:56:07 UTC
I just remembered that i have the Kwin script "force blur". Disabling it the issues goes away, although i really want blur on Firefox. I guess the problem here is in the script?
Comment 2 sk.griffinix 2020-05-29 05:45:19 UTC
This (In reply to Azarilh from comment #1)
> I just remembered that i have the Kwin script "force blur". Disabling it the
> issues goes away, although i really want blur on Firefox. I guess the
> problem here is in the script?

This simply means that a transparent element extends beyond window, which is usually not visible, but becomes so when blur effect is forced on the window
Comment 3 Vlad Zahorodnii 2020-05-29 06:06:05 UTC
Yeah, but maybe the blur effect could clip the blur region.
Comment 4 Vlad Zahorodnii 2020-05-29 07:48:16 UTC
Git commit 309fbf1837863c483b04491eda8af8bc5235260a by Vlad Zahorodnii.
Committed on 29/05/2020 at 07:42.
Pushed by vladz into branch 'Plasma/5.19'.

[effects/blur] Don't blur outside the frame rect

We need to clip the blur region to ensure that the background behind
client side drop shadows is not blurred.

M  +3    -3    effects/blur/blur.cpp

https://invent.kde.org/plasma/kwin/commit/309fbf1837863c483b04491eda8af8bc5235260a