The risks listed in the article itself mostly seem to fall under the same, non-AI-extension, core problem of "you're given them all your data." And that's a risk for non-AI-based extensions too, but if you look at the code of an AI one, it's gonna be obvious that it's shipping it off to a third party server, right? And once that happens... you can't un-close that door.

(The risks about copyright and such of content you generate by using AI tools are interesting and different, but I don't know that I'd call them security ones.)

The prompt injection one is pretty interesting, but still seems to fall under "traditional" plugin security issues: if you authorize a plugin to read everything on your screen, AND have full integration with your email, or whatever, then... that's a huge risk. The AI/injection part makes it triggerable by a third-party, which certainly raises the alarm level a lot, but also: bad idea, period, IMO.