Bug 494534

Summary:	Login theme can have illegible icons when using an icon theme that does not have all of the required icons
Product:	[Plasma] plasmashell	Reporter:	Filip Fila <filipfila.kde>
Component:	Theme - Breeze	Assignee:	Plasma Bugs List <plasma-bugs>
Status:	REOPENED ---
Severity:	normal	CC:	KDE, kde, nate, visual-design
Priority:	NOR
Version:	6.1.5
Target Milestone:	1.0
Platform:	Arch Linux
OS:	Linux
See Also:	https://bugs.kde.org/show_bug.cgi?id=429622
Latest Commit:		Version Fixed In:
Sentry Crash Report:
Attachments:	Example of the issue

Description Filip Fila 2024-10-11 14:05:38 UTC

SUMMARY
Dark-colored icons show up on the login screen when the user has synchronized an icon theme that is not globally installed or is missing some icons. This can be a problem when a dark color scheme is also synced, resulting in dark-colored icons on a dark background. 

What's happening is that the SDDM sync feature passes the name of the icon theme to SDDM and the Breeze theme's components try to use the icon theme for icons in buttons. When they fail to find the theme's icons, I assume they simply always fallback to using dark Breeze icons. 

STEPS TO REPRODUCE
1. Set a user-installed icon theme (such as those from GHNS).
2. Set a dark color scheme.
3. Synchronize SDDM settings with Plasma settings.
4. Log out* 
*don't test with sddm-greeter because it has access to the user directory

OBSERVED RESULT
Illegible icons.

EXPECTED RESULT
Legible icons.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Manjaro Linux
KDE Plasma Version: 6.1.5
KDE Frameworks Version:  6.6.0
Qt Version:  6.7.2

ADDITIONAL INFORMATION
I'm not sure what's the proper way to solve this. A quick workaround would be to edit the Breeze theme so that the icon colors always match the text color.

Comment 1 Filip Fila 2024-10-11 14:09:47 UTC

Created attachment 174691 [details]
Example of the issue

Comment 2 Nate Graham 2024-10-11 18:23:56 UTC

Ultimately the only proper way to fix this is to implement Bug 447171; marking as a duplicate of that. Anything else will be a half-measure that won't actually give the user what they want (i.e. their custom themes on the login screen).

*** This bug has been marked as a duplicate of bug 447171 ***

Comment 3 Filip Fila 2024-10-11 18:47:35 UTC

Yeah, that's a whole another box to open up. I'm wary of copying files due to security issues and tried to just pass config information whenever I could. But it would be pragmatic if user themes could be copied so SDDM can access them. 

Although I still would treat this bug here as a separate issue and keep it open because even if you do manage to copy themes, those with missing icons will have these dark fallback icons.

Comment 4 Filip Fila 2024-10-16 06:38:33 UTC

I rephrased the bug title so it relates to Bug 491118. It's partly up to themes to add missing icons, like Nuno did for Oxygen, but it's also a problem with Plasma Components 3 if it's doing a bad job of setting fallback icons. I believe this problem didn't exist with Plasma Components 2.

I attempted to hack the login theme so that icons fallback to white, but I can't set the icon color property for all of the buttons.

The obstacles begin at line 205 in Main.qml, where there's ActionButtons that don't accept this property. 

I guess if there is a way to rework these buttons into other components that support setting the icon color, the bug can be worked around in the login screen.

If there's no way, the bug should be transferred over from sddm-kcm to Plasma Components. CC-ing Kai Uwe who I think worked on this.