Firefox hangs on Windows 10
I have 3 PC's that have all been upgraded to W10, and all 3 also run FF and their default browser. On all 3 of these PC's FF hangs for no reason, and even more baffling they all seem to hang at around the same time. Most often I will minimize FF and walk away from the PC only to come back later and not be able to access FF. When that happens the FF window is almost slightly blurry, and the only buttons available in the window are minimize and close.
Yesterday I updated 2 of the PC's to FF 40.0.3 but FF still hung in less than 24 hours. The other PC is running FF 28. The only thing these 3 PC's have in common is that they've all been upgraded to W10 and they share some of the same add-ons. Any suggestions on troubleshooting this? I did try disabling Flash but that did not resolve the issue.