Rated 3 out of 5 stars

The extension is very useful for people who are curious about what font a page is using. However, my problem is that it slows Firefox down dramatically on my computer (Fedora 22, Firefox 39, 2.2 GHz dual-core with 2 GB RAM). I know, not a high-end machine, but without this extension, everything is pretty snappy. With this extension enabled, almost every page has the "Unresponsive Script" dialog asking if I want to stop the scripts on the page. I use several other extensions and none of the others have this problem.

This review is for a previous version of the add-on (1.1.1.1-signed).