Bug 467483 - Blur effect is applied to only top left quarter of SDDM screen
Summary: Blur effect is applied to only top left quarter of SDDM screen
Status: RESOLVED FIXED
Alias: None
Product: plasmashell
Classification: Plasma
Component: Theme - Breeze (show other bugs)
Version: 5.27.3
Platform: Other Linux
: NOR normal
Target Milestone: 1.0
Assignee: Plasma Bugs List
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2023-03-17 11:47 UTC by medin
Modified: 2025-05-13 12:27 UTC (History)
4 users (show)

See Also:
Latest Commit:
Version Fixed In:
Sentry Crash Report:


Attachments
Blur effect is applied to only top left quarter of SDDM screen (518.77 KB, image/jpeg)
2023-03-17 11:47 UTC, medin
Details

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Description medin 2023-03-17 11:47:37 UTC
Created attachment 157358 [details]
Blur effect is applied to only top left quarter of SDDM screen

The blur effect on SDDM wallpaper is applied to only a quarter of the screen. This happens at rate of 2/3 of total login attempts.  See attached image for more info.

Operating System: Manjaro Linux
KDE Plasma Version: 5.26.5
KDE Frameworks Version: 5.103.0
Qt Version: 5.15.8
Kernel Version: 6.1.12-1-MANJARO (64-bit)
Graphics Platform: X11
Comment 1 Bug Janitor Service 2023-03-17 12:33:46 UTC
Thank you for the bug report!

Please note that Plasma 5.26.90 will not be supported for much longer by KDE; supported versions are 5.27, and 5.27 or newer.

Please upgrade to the latest version as soon as your distribution makes it available to you. Plasma is a fast-moving project, and bugs in one version are often fixed in the next one.
Comment 2 medin 2023-03-31 18:16:28 UTC
This also happens after upgrading to :

Operating System: Manjaro Linux 
KDE Plasma Version: 5.27.3
KDE Frameworks Version: 5.104.0
Qt Version: 5.15.8
Kernel Version: 6.1.21-1-MANJARO (64-bit)
Graphics Platform: X11
Comment 3 Nate Graham 2023-04-04 18:54:53 UTC
Have you previously applied any kind of manual configuration changes to SDDM to make scaling work differently?
Comment 4 medin 2023-04-04 22:20:14 UTC
(In reply to Nate Graham from comment #3)
> Have you previously applied any kind of manual configuration changes to SDDM
> to make scaling work differently?

I don't change scaling on laptop 15.6", I'm always using 100%; what I did was simply changing the wallpaper, then I reset it to default.
Comment 5 Nate Graham 2023-04-05 14:35:55 UTC
How odd.
Comment 6 Nate Graham 2025-01-09 22:23:34 UTC
Well, I still can't reproduce it in current git master, which will shortly become Plasma 6.3. Are you still able to reproduce the issue in Plasma 6.2.5 or later? Thanks!
Comment 7 medin 2025-01-10 12:50:58 UTC
It's still repro even on external monitors, what I can confirm about the problem is that the blur effect sometimes flickers and tries to extend to take the full space in media widget and Elisa but it instantely reverts to only quarter of it, on SDDM it's a hit or miss, it either starts fully applied or to only a quarter of the screen.

It seems the algorithm that calculates the space where the blur should be applied is not accurate for some screens, instead of taking the full space it's applied to only quarter of it.

This is quite apparent when I change the tracks in Elisa and Media widget, some thumbnails are applied (in top banner and background) to its full space and others to only quarter of it.
Comment 8 Nate Graham 2025-05-08 16:13:41 UTC
Does it still happen on Plasma 6.3.4 or later?
Comment 9 medin 2025-05-08 21:23:52 UTC
I tried to logout and reboot many times, and It seems the problem is gone for SDDM.

But lock screen and other apps like Haruna, Elisa... are still suffering from blur effect being applied to top left quarter.

Operating System: Manjaro Linux 
KDE Plasma Version: 6.3.5
KDE Frameworks Version: 6.13.0
Qt Version: 6.9.0
Kernel Version: 6.14.5-2-MANJARO (64-bit)
Graphics Platform: Wayland
Comment 10 Lenzoid 2025-05-09 16:49:47 UTC
Hi, thanks for your bug report! Glad to hear the upgrade fixed the SDDM blur for you.

> But lock screen and other apps like Haruna, Elisa... are still suffering from blur effect being applied to top left quarter.

I'm sorry I don't understand what you mean. Can you please clarify? What exactly are you doing, looking at, expecting etc. If this is a different issue that has nothing to do with the SDMM screen, a new issue should be created. Thanks!

An interesting and quick thing to try would be to create a fresh user and try to reproduce the issue with that. That would rule out some weird issue due to configuration files. It's rare but it has happened.
Comment 11 medin 2025-05-13 12:27:19 UTC
(In reply to Lenzoid from comment #10)
> Hi, thanks for your bug report! Glad to hear the upgrade fixed the SDDM blur
> for you.
> 
> > But lock screen and other apps like Haruna, Elisa... are still suffering from blur effect being applied to top left quarter.
> 
> I'm sorry I don't understand what you mean. Can you please clarify? What
> exactly are you doing, looking at, expecting etc. If this is a different
> issue that has nothing to do with the SDMM screen, a new issue should be
> created. Thanks!
> 
> An interesting and quick thing to try would be to create a fresh user and
> try to reproduce the issue with that. That would rule out some weird issue
> due to configuration files. It's rare but it has happened.

Thanks, it's unrelated to SDDM, I will search if I or someone already reported them.