I've tried replicating this on two devices with and without a VPN, but both are Chrome. Could you please provide more details on it and perhaps a screenshot along with the certificate that it's using (perhaps could be cached on your end)?
Then I was back on my forum, but I got tied up and let it sit for a few seconds on the screen.
When I looked up all of a sudden avast popped up. The warning specifically said the domain I referenced.
I hadn't visited that domain.
After that I returned to administrata specifically to inspect that domain I recognised as one of the top links.
I visited the link, and as noted it has an xf closed account page.
Just telling it like it happened as weird as it is sounding. It was on my primary system and am on my phone atm. I will check in the morning to see if avast left it in the logs. And no, I haven't replicated it again.
I also tried to replicate this as soon as I saw the thread posted this morning, but couldn't replicate. ForumDiscovery and the link in the topbar worked for me at all times and still does now, I've not seen any issues.
A quick Google search does bring up a lot of blog posts and discussions of Avast false positives, so it could be an issue like that if you've not seen any problems since.