Functions just brilliantly on my Firefox for Ubuntu. No complaints so far: it does do even more than expected initially.

I'm puzzled why this has received such low reviews so far, because it does exactly what it says on the tin. The previous users need to RTFM (read the manual).

Firstly, unlike a lot of other bookmark add-ons it ONLY requests permission for bookmark access. Most similar addons sketchily include "access to all sites". IMO we should encourage competent devs who put thought into what permissions their addons actually need.

Second, it supports operators like AND, NOT, XOR, OR, etc. It can even do NEAR (within X words of your terms) or ADJ (same as NEAR, but in the original order of your terms). I'm not sure what other features you can demand for an extension to label itself "advanced".

Third, it ranks them, and shows you up to 30 results, and it's quick.

Fourth, once you combine it with a shortcut: https://support.mozilla.org/en-US/kb/keyboard-shortcuts-perform-firefox-tasks-quickly you basically have a mini-app-launcher built-in.

Hopefully the obviously uninformed previous reviews won't keep the author from updating this add-on in the future.