X64 W10, Anyone having issues with Firefox v50.0.2 (even .1) and Sandboxie sites freezing PC?

Everything locks I can't even use the mouse to escape. I have to use task manager. Thank you!

 

For starters, here's a relatively recent thread with a lot of info, some of it helpful to the OP. Restarting Firefox in safe mode may help narrow things down. Three bars at top-right, click question mark at bottom , then "Restart with add-ons disabled."

https://support.mozilla.org/en-US/questions/1146555

I've also had problems with this browser version 50.02. It doesn't seem as stable as previously. If you run PerfMon with Firefox open, what does it show with CPU, ram, etc.?

 

Although I didn't have the Flash plugin installed I ran the "total" flash uninstall. At least initially, this seems to have resolved the issue. Now is Flash still installed on Edge? If not, won't I get a Windows security update? Thank you for the help!

 

Flash is built into Edge, consequently you can't uninstall it. It therefore receives updates just like everything else in Windows. I would leave the updates to it alone. Internet Explorer requires more manual attention to flash player, specifically for update checks and clearing storage data.

https://helpx.adobe.com/flash-player/kb/flash-player-issues-windows-10-edge.html

Edit: This seems stupidly basic, but manually clearing entire browsing history WITH cookies and checking cache usage under "Advanced" tab/Network can work wonders sometimes.