2019 edit : znqa has been removed from the firefox addons ! I'll setup a ZN mirror if anyone is interested. I still use it daily and find it useful, maybe others will. Ping me if interested.
I finally made some updates to this add-on ! I added support for up to 4 zites and reworked the UI a bit so it's more compact and has less chance to block the actual content of the webpage when opened, the result looks like this :
Grab it at the usual location on clearnet : https://addons.mozilla.org/en-US/firefox/addon/znqa/
Feedback or add-ons ideas most welcomed :)