The addon is superior to the original userchrome toggle but on macos there's a bug, when you open a new window it doesn't recognize the original style (not toggled) until you switch to another window or app and come back. Really kind of defeats the purpose.
Edit: The second invisible character \u200b seemed to be the issue. \u200f works as intended for me.

Fix issue of the old extension. The shorkey failed to toggle the state.

It suddenly crashed and won't work even on reinstall. Maybe it auto-updated.

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