If you don't know what the userChrome.css file is, or how to edit it, please look it up on a Firefox forum instead of asking about it in this repository. Thanks!About Browser extension (Firefox, Chrome, Opera, Edge) to redirect urls based on regex patterns, like a client side mod_...
Extracted from #77: All FF versions apparently have a bug in chrome.tabs.query: it can't query extension's own URLs like moz-extension://extension-id. Before Nightly 55 it produced a warning in console and an empty result, but Nightly 55...