I recently noticed that some of my add-ons are not doing their jobs. I looked in about:addons and sure enough, they're disabled. I can flip the toggle to enable them, but if I refresh the page, their state is reverted. I have not found a way to actually enable them. I pressed the restart button after a pending update then tried everything again without change. I'm aware that some add-ons can be marked as potentially unsafe or incompatible with the current browser version. That's not the case here. Nothing in the UI indicates there's a problem. Many of the add-ons have the recommended trophy icon. I removed and reinstalled uBlock Origin and Dark Reader. That seemed to fix it for now.