dispels (spellsteal ID:30449 and tranquilizing Shot ID:19801) don't seem to work anymore, although at least tranq shot did work a few weeks ago if i remember correctly.
even if i turn them to "inverted" the highlighted border shows up, but it doesn't disapper when it should.

Which version is failing and in which case ? I don't have any issue with Tranquilizing Shot.

This is fixed in AdiAddons/LibDispellable-1.0@e2a34a8
ABA update on wowace is pending

I can confirm that auras are not works for spellsteal on my mage, though I have not had any trouble with tranquilizing shot. This is for version 1.9 and I have checked that it is enabled under the option menu.

Spellsteal is currently not included in LibDispellable, which causes it to now show in AdiButtonAuras.

@Adirelle I have some other pending work on LD as well and would also include Spellsteal. Should be ready to PR later today or tomorrow evening, if that is ok with you.