Customizing Zulip CSS Dark Mode

Posted Thursday, February 26, 2026 by Sri. Tagged JOURNAL

SUMMARY // I have made a Dark Mode Zulip custom CSS file for the Zulip Desktop App that removes visual clutter and improves the contrast. You may find it a useful starting place for customizing your own Zulip CSS. The CSS and docs are available as a Github Gist.

There’s yet another uproar about Discord, the popular gamer voice chat service that has has grown into a community platform rivaling Slack and Teams. However, there’s been concern that the people-friendly vibe is turning corporate, which has put a lot of Discord users on edge. The first concern came when the company appointed a new CEO associated with predatory management. The latest hoopla with age verification has eroded user trust further, with many concerned that Discord will be destroyed by investment-driven leadership (e.g. ex-Activision leadership) that favors profit over people.

At the time of this writing, these Discord alternatives have also caught my eye:

  • Fluxer (open source)
  • Stoat (open source, formerly Revolt)
  • Root (closed source, though)

Zulip has grown on me, though, and with its maturity I may stick with it and deploy my own customized self-hosted fork.

I’m concerned too, and have started looking at open source alternatives. One of them is Zulip, which was mentioned to me by my friend Shannon. We’re trying out the free Zulip cloud version to evaluate it for personal projects, and after some initial confusion on my part I’ve decided I like it a lot! The only problem is that the user interface, while competently and attractively designed, hurts my eyes because of my sensitivity to contrast and visual noise.

Customizing

Zulip doesn’t support theming but if you use the Desktop App you can upload a custom CSS file.

I’ve collected my notes into Primer: Zulip Dark Mode CSS Hacks.