Pages are able to spawn new ad tabs

[Houkime]

Some pages can spawn new tabs with ads.
Their content is often blocked by qupzilla adblock, but they're popping nevertheless.
I've already consulted an issue here but it seems like popup blocker can't cope with them even with settings ok (although it does cope with basic popup windows).

Examples of pages that can do this trick (just some anime sites ^_^ ):

anitube.me (click on search field)
kissanime.ru (click anywhere - first time always pops)