Slack package has a dark mode, but current CSS for dark mode is broken for "All threads".
I add an optional argument to derivation for CSS url.
Default CSS url is an old one, so it is backward compatible.

What do you mean it's broken? Does the default url not work anymore? If it doesn't work, we don't need to be backwards compatible.

Slack package has a dark mode, but current CSS for dark mode is broken for "All threads".
I add an optional argument to derivation for CSS url.
Default CSS url is an old one, so it is backward compatible.

What do you mean it's broken? Does the default url not work anymore? If it doesn't work, we don't need to be backwards compatible.

Here is an issue laCour/slack-night-mode#218.
Personally I switched to fork.
But I don't think that all package users wants to switch to random fork.

What do you mean it's broken? Does the default url not work anymore? If it doesn't work, we don't need to be backwards compatible.

Upstream (of the dark mode) will probably fix the issues that currently exists after upstream (slack server side rendered html) broke the dark mode. But this would give more flexibility for the user of the derivation to "fix it" faster. I use dark mode myself at work and it's currently quite unusable on some pages.

And I think that this is a quite nice workaround to be able to patch it easily as a user of NixOS.

@anpryl Hey, could you rebase this on master? That would be great to solve the conflicts. Ping me when you done it so we can merge this PR :)

@etu rebased on master