Hide/Reveal Mask causing my browser to freeze

I am not using dynamic lighting, it has nothing to do with my map file as its happening on a blank page as well. I've tried enabling hardware acceleration. I am at my wits end trying to find any fix for this. This problem isn't affecting my roommate on the same OS and same browser and any troubleshooting is just pointing me towards dynamic lighting fixes. I am using Firefox as Roll20 will not load on Chrome for me. I am also using Linux Mint if that means anything.