I've had an issue on my Mac Mini since (I think) I bought it ~1.5 years ago. Firefox essentially stops responding randomly. When it happens, I can usually still scroll through the page, but I'm unable to click on any links on it. Other things like hovering over things that might change color also stops working. When it happens, it happens to all tabs that are open. It usually eventually comes back on it's own after a couple minutes. The weird thing is as soon as I load any other external application, even something as simple as Settings or Preview, Firefox will immediately spring back to life. Only a couple common addons (Ublock Origin) but it happens even with all add-ons disabled. It's sporadic, sometimes I can go all day without it happening, other times it happens every few minutes.

It's persisted through 3 different OS upgrades and countless Firefox versions. I've tried everything I can find about troubleshooting Firefox on mac and nothing works. It's not a resource thing as it happens with only Gmail open sometimes and Firefox being the only thing running. I'm at a loss and looking for anything that might help. I've never seen this issue on other Macs I've used Firefox with.