CMS theming not working with custom theme files

[poVoq]

Describe the bug
I configured a custom default theme for my instance, but I noticed that values for --cms-bg: and --footer-bg: in the custom light theme do not seem to take effect on the CMS landing page. Other settings like --sidebar-left-bg: for the CMS header colour or link colours work as expected though.

To Reproduce
Steps to reproduce the behavior:

1. Make custom light theme with CSS values for cms-bg and footer-bg
2. Enable custom light theme via CONVOS_DEFAULT_THEME env parameter
3. Navigate to CMS landing page
4. See error

Expected behavior
The custom theme should allow changing all colours of the CMS.

[jhthorsen]

This issue is impossible to figure out since it’s lacking in information.

1. How does the theme file look like?
2. Where did you place it?
3. What is the name of the file?
4. What is the value of the environment variable?
5. Are you sure those variables are used where you think they are?

[poVoq]

1. It is a copy of the original convos light theme but modified with different colours and a different name.
2. I put the custom theme file into /themes/ (the folder that is automatically created for such purposes in the data folder)
3. forgejo_color-scheme-light.css
4. CONVOS_DEFAULT_THEME=forgejo & CONVOS_DEFAULT_SCHEME=light
5. Yes as other colour modification in the same file work correctly and the browser inspector tells me these are the correct CSS variables.

I think this is somehow a question of ordering? It looks like the values set in the custom theme file are later overwritten again by some other part of the code?

[poVoq]

Ahh, looks like there is a duplicate of the footer-bg in the dark theme version of the same name.

A bit odd that this overwrites the value in the light theme.