Since there is only third-party ads, it's safe to use filters like this:

No regexp's, twice as fast.

Yeah, that would be better. In this case, it's not necessary to have specific folder filters.

webm files are type other ->
^$image,other
(or is there another way to also enable webms?)

Actually, WEBM files don't even fall into the "other" category at the present time, so you have to change permissions to allow WEBMs. Also, since Adblock Plus apparently no longer blocks images in /ad/ folders on the same domain anymore (at least on the versions I tested), the old custom filters are pointless now (unless you use youhate.us).

For WEBMs (there are currently only 15 that are blocked, though):

If you use gelbooru.com:


If you use youhate.us:


Note: this is the same as disabling Adblock Plus for gelbooru.com. You might as well use the dropdown Disable if it's just for Gelbooru. Or click on "Original image" off to the side to see the WEBM.