Plug in for Garmin GPS system is not compatible with FireFox 5.0?

''locking as a duplicate of this - https://support.mozilla.com/en-US/questions/851653'' I have updated FireFox plugins today. I have cleared download history. I have set up folder for downloads. Every time I go to Garmin and try to download to get current map updates a message comes up "Garmin Communicator could not be installed because it is not compatible with FireFox 5.0?