Arch Linux

MathB

Member

Registered: 2025-08-28

Posts: 6

[SOLVED] Plasma does not update SDDM's config.

Hi,

I just finished installing arch, and I installed the plasma-meta package to install kde as my DE.
I enabled sdd.service so that I get sddm at startup.

I went into plasma's settings -> colors and themes -> login screen (sddm) and clicked apply plasma's configuration, I got a confirmation dialog, clicked confirm then typed in my password.

However this did nothing, even after I logged off, turned the computer off and on, used the setting again...
Before you ask, the plasma-meta package does include sddm-kcm.

All I found is a post about someone on Endeavor running into the same issue because of some config files that they had left but this is a fresh install and they did not leave details :

Any ideas where I should look for for logs ? Is this feature broken (at least in the meta-package) ?
Thanks in advance for any help,
Mathieu.

Last edited by MathB (2025-08-28 14:57:04)

MathB

Member

Registered: 2025-08-28

Posts: 6

Re: [SOLVED] Plasma does not update SDDM's config.

After digging around in /etc (should have done that before the first post), I found the following problem :
Plasma is editing  /etc/sddm.conf.d/kde_settings.conf whilst SDDM is reading /etc/sddm.conf

I have no clue how to fix this though.

Scimmia

Fellow

Registered: 2012-09-01

Posts: 13,623

Re: [SOLVED] Plasma does not update SDDM's config.

Why do you have /etc/sddm.conf at all? You're overriding the one plasma is editing. See `man sddm.conf`

Last edited by Scimmia (2025-08-28 14:14:56)

MathB

Member

Registered: 2025-08-28

Posts: 6

Re: [SOLVED] Plasma does not update SDDM's config.

I checked that this file was empty and deleted it, I then used the GUI to 'apply plasma's settings' again and rebooted. This did not fix the issue.
I never created that file myself, it was created by installing the plasma-meta package.

Thank you anyways, that was a good idea.

MathB

Member

Registered: 2025-08-28

Posts: 6

Re: [SOLVED] Plasma does not update SDDM's config.

Okay, this is getting trippy, there also is a sddm.conf.d folder in /usr/lib rather than in /ect.

This time it contains a config file that is not empty.
I guess plasma is adding it's config file in the /etc/sddm.conf.d folder and sddm is using the /usr/lib/sddm/sddm.conf.d folder
How is this the default behavior right after installing the plasma-meta package ? is this a bug ? How should I get plasma's button to work ?

Scimmia

Fellow

Registered: 2012-09-01

Posts: 13,623

Re: [SOLVED] Plasma does not update SDDM's config.

I don't see how it's trippy when it's clearly listed in the man page.

MathB

Member

Registered: 2025-08-28

Posts: 6

Re: [SOLVED] Plasma does not update SDDM's config.

Well, I mean having two config files by default, one of which is empty...
Just why are two of those directory where one could put a .conf file being used ? And why an empty file ? Anyways I guess it just seems weird to me because I am a beginner.

MathB

Member

Registered: 2025-08-28

Posts: 6

Re: [SOLVED] Plasma does not update SDDM's config.

Thanks for your help and for the learning about config files.
I solved the issue,
sddm-kcm visibly does not set a value for Current=theme in the config file it creates when you are using plasma default breeze theme, I added manually.

[mathieub@ideapad16 ~]$ cat /etc/sddm.conf.d/kde_settings.conf 
[Theme]
Current=breeze
CursorTheme=breeze_cursors
Font=Noto Sans,10,-1,0,400,0,0,0,0,0,0,0,0,0,0,1

Should I report that somewhere as a bug ? If so where ? And how ?

SparcBR

Member

Registered: 2025-11-21

Posts: 2

Re: [SOLVED] Plasma does not update SDDM's config.

Something isn't quite right for sure.
Sorry to highjack but I was trying to make numlock on at login screen.

grep -i num
/usr/lib/sddm/sddm.conf.d/default.conf:Numlock=none
/usr/lib/sddm/sddm.conf.d/default.conf:# Number of users to use as threshold
/usr/lib/sddm/sddm.conf.d/general.conf:Numlock=none
/usr/lib/sddm/sddm.conf.d/dr460nized.conf:Numlock=on

it wouldn't turn on, even if I use /etc/sddm.conf, nothing works

So I commented the line /usr/lib/sddm/sddm.conf.d/general.conf:Numlock=none and now it works..