[omoikane]

I tried in Chrome Incognito mode and I have yet to encounter a popup, but I only sampled a few persons and only scrolled for a few minutes, so I am not sure if they only reduced the threshold or if it's not yet rolled out everywhere.

[bombcar]

I wouldn't be surprised if it somehow sees in the cookie that you've logged in before and prompts to login.

I've not seen one for awhile now, but I have no logged in ever.