This page’s appeared twice in the last 10 minutes, when I used the nav buttons on the mobile site to try to go to Active & Threads I’m On. I’m using Safari on an iPhone 7.
I clicked on the More Details link & it came up with a warning about your SSK certificate being out of date. Which seems a bit odd because I’ve only ever heard of SSL certificates. Anyway - something funny’s going on somewhere. I’m about to run a virus check on my phone & I’ll update with the results.