Freezing can occur for many reasons. With sites that display a lot of advertising, this can include waiting on third party servers and ads that invoke the Flash plugin or another plugin. We have a general support article that might be relevant: [[Firefox hangs or is not responding - How to fix]]. If you get dialogs reporting that a script is running slowly, this article might be more applicable, and if you allowed scripts to run forever, please undo that change: [[Warning Unresponsive script - What it means and how to fix it]]. Another common cause of unresponsive script errors on Windows 7-10 is the protected mode feature of the Flash player plugin. That feature has security benefits, but seems to have serious compatibility issues on some systems. You can disable it using the Add-ons page. Either: * Ctrl+Shift+a * "3-bar" menu button (or Tools menu) > Add-ons In the left column, click Plugins. On the right side, find "Shockwave Flash" and click the More link. Then ''uncheck'' the box for "Enable Adobe Flash protected mode" and try that for a day to see whether it helps. ---- Regarding the logged event, maybe this thread is relevant, I can't tell for sure: [https://answers.microsoft.com/en-us/windows/forum/windows_8-performance/event-id-10016-the-application-specific-permission/9ff8796f-c352-4da2-9322-5fdf8a11c81e?auth=1 Event ID 10016 - The application-specific permission settings do not grant Local Activation permission for the COM Server application with CLSID - Microsoft Community] ---- More generally, however, if Firefox causes a system restart that would usually be related to a severe incompatibility with a device driver such as a display or print driver. Windows usually can prevent applications from causing such issues on their own. Could you try disabling Firefox from using hardware acceleration? Since this feature was added to Firefox, it has gradually improved, but there still are a few glitches as new features are added and drivers update. "3-bar" menu button (or Tools menu) > Options In the left column, click Advanced. On the right side, with the "General" mini-tab active, uncheck the box for "Use hardware acceleration when available". This takes effect the next time you exit Firefox and start it up again. Users may notice degraded font smoothing and reduced video performance with this change but perhaps it will prevent these extreme events. You might want to check whether graphics card/chipset driver updates are available for your system. This article suggests safe ways to do that, although some users have said that Lenovo requires their own drivers which may run behind Intel's updates: [[Upgrade your graphics drivers to use hardware acceleration and WebGL]].

Thanks for the post! I'll try some of those changes tomorrow morning and I'll let you know if the issue persists!

The issue didn't make too much sense, but we ended up uninstalling Firefox and the issue hasn't come back yet. Shame because I love the browser, but it's an easier solution for the public PCs. Thanks for the help!