Does it work: 1) in safe mode: https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode 2) with a fresh profile: https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles

the video is black no picture or sound

Does it work in safe mode?

cant find menu button to refresh

You can check the log in the Web Console for error messages and the Network Monitor (Firefox/Tools > Web Developer) to see if content fails to load or is possibly blocked. *https://developer.mozilla.org/Tools/Web_Console *https://developer.mozilla.org/Tools/Network_Monitor Use Ctrl+F5 or Ctrl+Shift+R to reload the page and bypass the cache to generate a fresh log. ---- If you use extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) that can block content (e.g. Adblock Plus, NoScript, Flash Block, Ghostery) then make sure such extensions do not block content. There is security software that can interfere with loading content, so check that as well. Start Firefox in <u>[[Safe Mode|Safe Mode]]</u> to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration is causing the problem. *Switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Appearance *Do NOT click the "Refresh Firefox" button on the Safe Mode start window *https://support.mozilla.org/kb/Safe+Mode *https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes