This makes neither sense nor can I confirm the YouTube issue. There is no relation at all between having this extension enabled and using YouTube. Also „some other glitches on other sites" makes no sense at all because this extension doesn't execute any code on websites. So it's just not possible. I also don't believe you the "crashing" part as the extension just uses WebExtension APIs and if it were true, a lot of extension would cause crashes. Another fact: There are more than 60,000 active users of the extension and there is not a single report for any of these issues.