Greasy Fork

Problem with non-English versions of Firefox

Script doesn't work on non-English versions of Firefox in the following situation:
-clicking on YouTube search results (example) with left mouse button opens link in the same tab with autoplay turned on (except for English versions of browser)
-clicking on search results with middle mouse button opens link in new tab with autoplay line and button completely absent; autoplay doesn't start (English versions of browser show autoplay line and button correctly)

Thanks for the feedback.
I've updated the script, it should work as expected now.