In FF browser click on Tools, then Add-ons, go to plugins, find OpenH264 Video Codec..., in drop down window click on "Never Activate" and then click Options and turn "off" automatic updates.

Let me know if this helps.

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

• Switch to the DEFAULT theme: Firefox/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

cd1515 said

i just see a black box and nothing happens when i click it

thanks to southern style and cor-el for the suggested fixes but neither one worked. same issue remains.