I'm currently receiving a weird JavaScript error on my error monitoring tool Sentry that says can't redefine non-configurable property "userAgent".
It seems like the error is happening on multiple pages but only on Firefox. Additionally, on all errors the referrer page seems to be "https://www.startpage.com/".
However, I'm not able to reproduce the error and have no clue whats causing the error as I do not have any assignments to the navigator.userAgent var.
Does anyone else have this issue, too, or has any clue what could cause this error?