Has anyone had the RMBrowserAddOn installed in Firefox but not recongized by RM when trying to edit a use-case diagram?

We are still running on CLM 4.0.2 (working on upgrading to 5.0.2) and have just ran into a problem with some of our RM users.  They are using the RMBrowserAddOn to edit Use-Case Diagrams in the browser.  Our IT department has deployed Firefox ESR Version 31.3.0 to some of our users.  When they go and try to edit the diagram, RM tells them they need to install a plug-in.  They go through the steps to install the plug-in, including restarting Firefox.  They come back to the diagram and click edit and are again prompted to install the plug-in.  Checking the Add-ons manager in Firefox, the RMBrowserAdOn 4.0.2.0_0 shows to be installed.   We checked with other users who are on ESR 31.0 and the a plug-in works fine.

I know that Firefox ESR 31 isn't officially supported, but I thought I would see if anyone had seen this type of behavior before and if they knew of a way to fix it.  We can roll back to 31.0 for this user if absolutely needed, but I was hoping there was something else that we could do...  We have seen similar behavior in IE 10 (IE 9 works okay).

Thanks,
Jamie.