Doesn't work on all machines for unknown reasons Rated 3 out of 5 stars
Doesn't always work but great when it does. I use this to make some SEC files with txt extensions, plain/text content-types, and HTML-encodings look right.
In some computers where I have installed the program I can get this add-on to work and others not. I've tried clean installs, re-installation of Firefox, and tweaking the options and nothing works when it doesn't install properly. I had one friend successfully install it and another fail. All on Windows and all with the most recent Firefox. As far as I can tell there is no support system to get it to work, so that really takes away from the benefits of the program. I also was unable to successfully get the program to work on Ubuntu.
Still, when it works it does exactly what I want and it is free.