Please add regex and/or wildcards to Thunderbird filters. I know its been suggested and requested and discussed on forums hundreds of times, yet Mozilla has never added either option. One of the most powerful anti-spam and anti-scam filtering possible involves filtering by IP address ranges in the "Received" message headers, which we can all see plainly when we examine a message with "all headers" view selected. Quite often if you use a "whois" lookup on the IP addresses in SPAM mail, you'll quickly find the offending IP in a range of addresses from a country you have no interest in hearing from. But trying to "Match" ranges of IP addresses without REGEX (or at least wildcards) is nearly impossible. Yes, I know there is a 3rd party program called "FiltaQuilla", but it simply does not work. I've been back and fourth with the authors and developers of and that add-on it is incapable of seeing the email header Mozilla calls "Received", as it simply does not exists in the header database (manually adding it in the system registry does not help). There are no easy work around to this. Please add this capability.