Stuck UserAgentString

Just fixed a bizarre issue with a workstation that I figured I'd post here, just in case anyone ever runs into anything like this (I found nothing through google). We're utilizing Tenable NNM to do passive monitoring, and for a while my workstation has been lit up with criticals from an old version of Chrome (specifically: User-Agent: Chrome/70.0.3538.102). Chrome's very up to date and there's no other old version, so this immediately leads to a rabbit hole. After some off-and-on sleuthing, I asked chatgpt what it thought, it suggested downloading Fiddler which I had never used before. Turns out basically all my web requests were using said old Chrome useragent string. Hopped into chrome's developer tools, set to default. Changed it to a custom string and threw in the version it claimed I was using +1, monitored for the new version, new version appeared... so that was working. Set back to default, and now all my requests have the appropriate string instead (User-Agent: Chrome/119.0.0.0). I can't fathom when this would have changed, or how it would have been stuck, but if you're ever wondering why you've got 500 criticals in a passive scanner for an out of date browser, check this first.