Hello Jean-Ricky, yes, as you say, this is a known regression introduced by Firefox 146.0 :-(
This is discussed here https://github.com/aaFn/Bookmark-search-plus-2/issues/344 as you highlight.
It seems that a hardcoded workaround will be needed until Firefox fixes the regression or provides a better function on its API. I should provide that next week-end, as I am currently travelling.

For your suggestion, would you mind adding it as an enhancement request on https://github.com/aaFn/Bookmark-search-plus-2/issues/, so that I can track it there ?

Thank you, aaFn.

--------------------- Edit on 22/12/2025 ---------------------
Hello , I found a way to not "hardcode too much" by referring to FF internal CSS variables.
In addition, this is improving the handling of when the Theme is "System default", and the system theme is in dark mode.

This is in 2.0.137, published now, all should be fine.
Let me know if any problem, thank you, aaFn.