I've updated znqa to support adding one (for now, more to come) custom zite to the icon list ! It also has a proper option page and browser menu icon.
You can grab it at https://addons.mozilla.org/en-US/firefox/addon/znqa/
As usual, the source is under MIT/X11 on Gitcenter : http://127.0.0.1:43110/1NaRTgwxsn17BCVSfvq6LG8NVPb9srKG5X
Next up will be fixing the icon list placements which may be a bit off depending on your resolution and adding support for multiples custom zites !
Thank you to the person who put a kind review in the Mozilla Add-on page :)
As usual, feedback much appreciated !
edit : A version 0.1.5 has been released shortly after with the following fixes/improvements :