Indeed, this is why I eventually stopped using it; sometimes a random site wouldn't function properly, and took time to figure out it was uMatrix. It was a nice plugin indeed though.
Yeah true, but I had many sites that I manually white-listed scripts / external resources, and was succesfully using those sites. But then some particular functionality of the site you rarely use once stops working, and you later find out uMatrix was still messing with some stuff, even if you whitelist all resources.