Only partially modifies the styling, but does it very poorly. Seems to be partially broke as of now, some parts are white, fonts have weird red/blue anti-aliasing... Not usable imo.

A good dark theme isn't 100% black. Also it blacks out the document background too and has zero options.

I have read this same yet:
when you turn back to light mode, cursor becomes invisible and that's too bad.
Also is true, in dark mode the icons aren't clear visible, they becomes confusing.

By the way, this extension is a very good idea. Improve it, and you could reach 5 stars.
good job.