This add-on is not actively monitored for security by Mozilla. Make sure you trust it before installing.

Ive tried all IDM suggestions and the downlaod box still missing from youtube, so cant download

Won't work on FF regardless of what version including Portable versions.

Works seamlessly on Chrome though. I tried the instructions to manually install the file. It get's loaded but won't appear in the tool bar and it won't execute when trying to download a file.