Rated 4 out of 5 stars

This add-on works very well and fast for unencrypted connections. Sadly it does not function (stuck after LIST command) for FTPS in my case where other tools don't have problems.

This review is for a previous version of the add-on (2.0.16.1-signed). 

This is a known issue with Firefox (in conjunction with some servers). Unfortunately there is no current workaround - hopefully Firefox will fix this in the future!