To be fair, blocklists are not really lists of regexps. They contain some regexps indeed but the syntax is mostly custom and matching relies on both patterns fo

To be fair, blocklists are not really lists of regexps. They contain some regexps indeed but the syntax is mostly custom and matching relies on both patterns found in URLs (This part could be partially expressed as RegExps) as well as a multitude of other things like constraints on domain of the frame, domain of the request, type of network request, etc.