Firefox 40 which is now a Beta channel version is slated for Release on 08-11-2015 - next Tuesday, will be more compatible with the last minute changes in Windows 10 than is the current Firefox 39.0 release which has been around for 5 weeks now.

https://www.mozilla.org/en-US/firefox/40.0beta/releasenotes/ https://www.mozilla.org/en-US/firefox/channel/

What you're describing could indicate an incompatibility between Firefox and your graphics card/chipset driver software. That software probably was updated with Windows 10, and as noted in the earlier reply, Firefox 39 doesn't have all the compatibility fixes.

If you are not inclined to try the beta test version of Firefox, could you test in Firefox's Safe Mode? That's a standard diagnostic tool to deactivate extensions, hardware acceleration, and some advanced features of Firefox. More info: Diagnose Firefox issues using Troubleshoot Mode.

If Firefox is not running: Hold down the Shift key when starting Firefox.

If Firefox is running: You can restart Firefox in Safe Mode using either:

• "3-bar" menu button > "?" button > Restart with Add-ons Disabled
• Help menu > Restart with Add-ons Disabled

and OK the restart.

Both scenarios: A small dialog should appear. Click "Start in Safe Mode" (not Refresh).

Any improvement with the display glitches?

I downloaded the 40 beta and it seems to be working.

I appreciate your help,

Michael B.