See https://bugzilla.mozilla.org/show_bug.cgi?id=820759#c12
Thomas Ng (from oracle.com) wrote this 2012-12-24 14:50:48 PST
I can reproduce now! At least with this setup:
7u5 + FX 2.1.1 installed first.
Install 7u10 -> this will cause plugin registration problem. Looks like we have a bug in deploy registration code to handle this case. Plugin from 2.1.1 is still being registered as fault. I need to debug more to find out the problem.
In my case, uninstall of FX 2.1.1 will correct the problem and bring back 7u10 as default plugin.
Also, 7u5 upgrade to 7u10 works okay for me. (no FX 2.1.1 standalone install) 7u10 plugin gets registered correctly.
Would be great if Mozilla can confirm this is what they are seeing as well. Thanks!
I added this fix to http://kb.mozillazine.org/Java#Uninstall_JavaFX