Since the quantum update, imdb-search add-ons don't work anymore. They just open an empty tab. I'm using the Add-On "imdb search selection" as well as another imdb search addon (which seem to be up to date and for quantum). The weirdest part is that I could'nt even use bookmarks to the site, but that problem suddenly seems to be fixed now. Other search add ons (Wikipedia, Amazon, Leo dictionary) work fine, though.

Did not find anyone else addressing this problem on the web.