Is it possible for extensions to change individual tab colors in the native tab interface?

[hellmouthxyz]

Background:

A common annoyance that I experience, especially at work, is having a bunch of tabs open from the same domain while one of them remains more significant to my workflow for a little while. I've always wanted the ability to temporarily change the color of individual tabs to make them easier to see.

My understanding is that Firefox does not support changing individual tab colors. Users that wish to change a specific tab's color have to use extensions that replace the native tab list completely. Users can change individual tab colors in Sidebery and an extension is available to add the same functionality in Tree Style Tabs.

I like Zen's native tab interface and I don't really want to replace it with something like Sidebery.

Question:

I am not familiar with which aspects of Firefox are used by Zen, so I don't know if Zen shares Firefox's foundational limitation on individual tab colors. Is it possible for an extension to temporarily change the colors of individual tabs in Zen's native tab buttons?

No such extension exists, as far as I've found, but if it's at least possible to do, I wouldn't mind making it myself. It would just be helpful to know if it's even possible to implement this in an extension since it's not possible in stock Firefox anymore.