Annoying, Buggy and Awesome Rated 4 out of 5 stars
I've never liked things popping up when I select words since I select words all the time to keep my place while reading, however that was easily disabled.Easily disabled provided you are using a website with a WHITE background. If you try using it on a website the a dark background it's impossible to read the options.However, being able to use regular expressions to search pages is AWESOME!! I've been waiting for a plugin to do this for years.So thank you very much kind sir :)
Edit: Unfortunately I am unable to take a screenshot of the options menu. When I try to take a screenshot the options menu disappears. The issue is that the background appears transparent. It might be a Ubuntu or Linux issue, I assume you use windows.
Don't take it personal, I rarely give 5 star ratings.
The options are perfectly readable on sites with dark background - which site didn't work for you? I haven't found one not working. UPDATE: I've tested FS on both Ubuntu (in VirtualBox) and RH Linux before, and didn't see any background problem. So it's likely related to the specific website you went to that may have a CSS rule overriding Addon SDK's panel's CSS, which, if happened, is more an Addon SDK issue. Anyhow I need to reproduce it to fix it. END UPDATE
Frankly, simply because this addon is practically the only usable/correct FF addon that does regex search for you, IMO it should already deserve a 5-star from a regex user's standpoint - if this feature was easy, why Firefox/other addons don't do it?