There is a slightly annoying advertisement box outside of the video in the newest YouTube redesign:
Here's a link to the example video I used in this case, but the box appears on many other monetized videos.
If I add a filter, it adds a very long advertisement string to my filter list. This string is probably unique.
I've tried blocking elements like these before. The elements are usually back after a page reload.
How do you block these unique elements? If I block its container - which has the nice name ##container - it's going to block every single container on the site, leaving me with only the video.