That did the trick. Thanks for your help :3

Well, technically, I can download them, but only with the green button (in 720p) or through the website. As for the screenshot - here you go: https://i.ibb.co/wRYsDS0/New-Canvas1.jpg - as I said before "Download..." text just hangs there forever, never progressing into giving me a drop down menu as it used to. And currently it is the case on every video.

Did it. Didn't help. In fact now it says "Download..." forever on all videos, even on videos that used to work before.

I spoke too soon saying that drop down menu works now. So apparently it works on half of the videos and on half it doesn't, and I just had a streak of videos that had a working drop down menu, so it seemed to me like it worked everywhere. In reality some videos return a working drop down menu and on others it just says "Download..." forever. It seems random on which videos the drop down menu will work and on which it won't, but it's consistent, in a sense that if a video returned a working drop down menu it will continue to do so, and if it says "Download..." forever, it will continue to do so forever.

Just some random examples:

These videos have a working drop down menu (at least it works for me): youtube.com/watch?v=gnGAjiALurI youtube.com/watch?v=qS-LXvhy1Do youtube.com/watch?v=-PdbT1NTbcE youtube.com/watch?v=z0eSyLb6FE0 youtube.com/watch?v=lSPqQ68mf-w

And these videos say "Download..." forever: youtube.com/watch?v=HOE-JssEr5A youtube.com/watch?v=HkPMaRAjfc8  youtube.com/watch?v=HN8DFyxH6YY youtube.com/watch?v=d5c-doEr9Ic

A same channel could have a video with a working drop down menu right next to a video with "Download... forever" video.

Also on music videos the whole thing doesn't work, even the big green button, but I can still download them through the website.

Here's the info:

Browser: Firefox 71.0 Windows

User Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:71.0) Gecko/20100101 Firefox/71.0

Extension: ff 8.61

Actually a day after I posted about the bug drop down lists started showing up again. Which is weird, they weren't working for me for maybe more then a week before that, but now they do. I don't know why and I don't know why they didn't all that time prior. However the left click still does nothing when I try to click on download options in the drop down menu. It does respond to clicking "more" and "ummy" options, but nothing else.

Great. Thanks for the quick reply.