is negative lookahead supported?

[8712staefa]

Negative lookahead (?!.....) does not seem to work in Mac Firefox 71. I get slow down warnings even after 40s (default 10s).

[SethFalco]

I've just tested this and found that negative lookaheads appear to be working fine. I'm using Ubuntu 18.04, Firefox 85.0.1 (64-bit).

I tested this page with Negative(?![ (]) which failed to find any results. Whereas Negative(?!F) successfully matched the word in the issue title and first comment.

It'd probably have helped to include an example webpage and regex so the issue could be reproduced.

Edit: However, I have occasionally received "slow down warnings" after using it. I am yet to determine what the cause is. It can easily be achieved by just spamming "Search" a couple of times while nothing is typed in the "Regular Expression" field, though.

Edit: Actually, the "slow down warnings" appear a lot, and the extension eats a lot of CPU, even when it's not in use. :thinking: