This is a much needed tool for Youtube - thank you for making it! Unfortunately it isn't working perfectly so one needs to pay very close attention while using it. For example when a longer list is loaded and one starts to select items from it and keeps scrolling down, when more videos get loaded in, they get randomly selected as well, so one has to start over... Unless it goes unnoticed, because then it makes a huge mess.

Also after removing selected items from the list, sometimes there were items (videos) left on the list which should have been deleted.

I was sorting out a huge list with over 4.000 videos on it and this add-on cut down the time needed to do so to about 1/5. But if it worked flawlessly, it would've cut down the time to perhaps 1/20.