Weird issue involving Intellij and attempting to log in to account to use AI

I just had the weirdest freaking thing happen. I was going to work on some scripts I'm developing, so I opened Jetbrains. When the separate window for their built-in AI code assist opened, it said I needed to log into my account to verify licensing, which was odd because I used it yesterday. It was logged in and usually remembers login info and auth tokens.

I'm thinking, 'eh, maybe cookies got erased or something like that,' so I click the login button, and JB launches the browser as usual. Instead of the standard login screen on JB's website, I'm presented with a certificate error saying that the cert identity doesn't match the host; therefore, I cannot continue. I'm familiar with the error, so I open up the cert info in the browser to see what site the cert matches. Upon doing so, I see that the cert belongs to '*.taylorfrances.com', a site I've never visited or known existed. At this point, I'm thinking, 'What is going on here?' so I instantly reboot the laptop, and after rebooting, I go directly to JB's login page. There is no error this time; the cert CN now says account.jetbrains.com, and everything works.

I'm a bit freaked out. My questions:

1. Could the source of this event be on my side? A rogue mitm proxy or similar?
2. Where do I start if it's on my end?

This is the first time I've seen this except for misconfigured certs/servers on my end, so I'm a little surprised. I would appreciate any thoughts or input you can share. My OS is KDE Neon, and it has all the latest patches.