Good tool so far! Rated 4 out of 5 stars

When I visit family, I'm very annoyed to find any 404 errors suddenly leading to their ISP's (inferior) search page -- and when I was searching from the address bar, their ISP hijacked that, too, so I had to go in and change my about:config keyurl back to google -- but I like to see the 404 errors and I like to be able to "correct" them if possible -- especially if it's because the site mistyped the URL in a link, for ex., by leaving out the colon or putting the http:// part in twice -- and without having to go back to the original page to see what the error was.

My family's ISP wasn't listed, but I was able to get NoRedirect to work easily by deliberately typing in a bad URL and copying the first part of the URL. I then substituted "(?:[^/]+\.)?" for the first element of the URL, since it was obviously one of a set of servers used by Frontier (oops! did I just name the naughty ISP?), and now when I type in a bad URL, I get a nice 404 message, just like I expect. Maybe I'm just old-fashioned, but I really don't like ISP's hijacking my browser like that. *grumpy face*

NoRedirect is easy to use and configure, but I think it should come with some kind of directions. I'm pretty good at figuring this stuff out (I had no idea what PCRE was before using this extension, and still don't really know), but I'm sure that many users would be well-served by a few user-friendly instructions on how to add an ISP that is not already on the list.

Thanks for the useful tool!