Just like it says, Pandora won't load past the blue splash page in Firefox. I have whitelisted it for cookies, cleared cookies and disabled every extension with no change. It *will* load in "private" windows, though--and I even had to post this from a private window; when I tried in a normal window, the sign-in redirect for the community also hung on the splash page.
Well, no idea what exactly was causing it, but "refreshing" Firefox so it removed all extensions did the job; I suppose I might figure out which one was causing it as I re-add extensions...
Just checking in @Nonmouse, are you able to load Pandora on your Firefox browser?
If you're still having trouble I suggest running our Firefox Troubleshooting steps to get Pandora up and running on your PC.
Hope this helps, let us know if you're still having issues.