Never used Comet but what is that diferent from any web site sending information to google-analytics[.]com?
Worst, you visit everyday sites with Facebook pixels and they get to know where you are and do.
This would be akin to Chrome sending the user's (unmodified) URLs to Google. Even Chrome thinks that that would be really bad for user privacy, and goes through elaborate techniques to not leak the user's direct browsing to Google, even for security-positive use-cases like Safe Browsing.