In a plugin, how does one add a per-user CSS? E.g. caused by a user setting? Adding the styles and whatnot to elements/via stylesheets would be global, no?

What are you trying to do? You can do things like change individual username/mention color just through the normal theme CSS. If you mean like, change some specific part of a theme with a toggle through a specific users preferences I don’t believe you could do that without giving them their own them…

Like for example, a per-user setting to change fonts of certain things (e.g. the Markdown composer).

You could offer groups that the user can join and use CSS Classes for Current User's Groups . Or the user can use a browser plugin to change CSS only for themselves. I use Stylus to customize my experience on Meta. Was the composer a random example? Or what do you want to offer in addition to “Use …

[image] Moin: Was the composer a random example? Kinda. I was thinking how the font would be changed per-user.

You can probably achieve this in a plugin by doing something along the lines of: with the plugin API add a api.addSaveableUserOptionField("composer-custom-font") add the field to the UserOption table in the db and the serializer so it can be set add a connector to the user’s interface page so the …

Add per-user CSS in a plugin?

Development

NateDhaliwal (Nate Dhaliwal) August 9, 2025, 9:04am 5

Kinda. I was thinking how the font would be changed per-user.

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Add per-user CSS in a plugin?

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