Perhaps even better if there is a setting so distros can configure this kind of stuff :-)

This is the idea. There is currently only one option in the settings (https://github.com/sddm/sddm/blob/develop/data/man/sddm.conf.rst.in#L81) and would either need to make that a list or to add a "System Themes" / "User Themes" option.

How about we make Current accept being an absolute path?

I don't see how we benefit from the ThemeDir + Current distrinction.

How about we make Current accept being an absolute path?

I don't see how we benefit from the ThemeDir + Current distrinction.

Could be done, but IMO sddm should have a default location for themes outside of /usr. If that's not provided somehow, this is entirely up to the user or configuration tool, which is IMO the wrong place.

What I mean is that it feels wrong to ask SDDM to be figuring out at runtime where to get the theme from.

If the users want to have sddm use a theme located elsewhere, they should be able to just inform which directory it's on.

What I mean is that it feels wrong to ask SDDM to be figuring out at runtime where to get the theme from.

Yeah, and ideally SDDM provides a location OOTB where all configuration tools (I guess just sddm-kcm, can anything else install themes?) can look for it and write to.

If the users want to have sddm use a theme located elsewhere, they should be able to just inform which directory it's on.

In theory that could mislead users (or worse, tools) to select some location inside $HOME, which can be insecure.

IMO doing it like SessionDir in PR #1543 and allowing multiple directories to be specified (with one being inside /var, /usr/local/ or maybe /etc) is the most straightforward and obvious option.

IMO doing it like SessionDir in PR #1543 and allowing multiple directories to be specified (with one being inside /var, /usr/local/ or maybe /etc) is the most straightforward and obvious option.

Definitely agree with this approach with the paths from my first comment.

In theory that could mislead users (or worse, tools) to select some location inside $HOME, which can be insecure.

Having a ThemeDir can also mislead users to thinking they should be using home. I don't see why we need to make it more complex than it needs to be.

Since SDDM will be joining KDE and KDE Plasma 6 is in development, might this be a good chance to implement or otherwise change where the SDDM themes are located?

+1