Rated 5 out of 5 stars

How to update.
1. Save link as.
2. Open the .xpi with winrar,7zip, or whatever you use.
3. Open the install.rdf no need to extract it since it can be opened with notepad.
4.At line 17 which reads <em:maxVersion>3.6.*</em:maxVersion>
Change the 3.6.* to whatever you're using no need for the second . or *. Example <em:maxVersion>20.0</em:maxVersion>

The * can be used though it's for wildcards. I usually put 20.0*

This review is for a previous version of the add-on (1.0.3). 

Just updated the actual plugin, hopefully gets reviewed asap. Sorry for the trouble!