Works fine for me. Any chance that you are blocking 3rd party cookies?

Make sure your Java (Not JavaScript) is up to date Verify Java and Find Out-of-Date Versions {web link}

Version 8 Update 66 Release date November 16, 2015

I don't think that third-party cookies should matter because I've never noticed difficulties (I normally use the 'from visited' choice).

Can you post a link to a publicly accessible page (i.e. no authentication or signing on required)?

Start Firefox in Safe Mode to check if one of the extensions (Firefox menu button/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem.

• Switch to the DEFAULT theme: Firefox menu button/Tools > Add-ons > Appearance
• Do NOT click the Reset button on the Safe Mode start window

• https://support.mozilla.org/kb/Safe+Mode
• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes