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CloseReview for Tab Wheel Scroll by Nekstati
Rated 5 out of 5 stars
In Firefox 57+, I use AutoHotKey script to replace this addon:
https://gist.github.com/8ace06628f0f0ea66ff09c5e547088df
Script has exactly same functionality - it switches the tabs by mouse wheel when cursor is over the tab bar - no need to hold right button or something.
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