I'm having a new issue (adding to the blue background above the thread content and the gargantuan/fuzzy avatar) which I thought I was seeing before but now I'm sure. I very often click on a thread title to go to first unread post, or else use people's reaction (likes) to see which of my posts is liked. That doesn't normally skip past unread posts since my liked post is above those.
I do not click on the notification of one of my quoted post because that is very likely past the earliest unread post. But often (always?) I'm not seeing some unread posts in that latter case. If I use the thread title to go to the first unread, it goes way past that post and there are a ton of unread posts I don't see.
I am downloading the latest macOS update and I wonder if what we're observing with the blue screen and massive avatar is due to elements being downloaded that should be hidden but appear too early because of timing delivering the CSS and JS. With the competition for my download bandwidth, I have seen this more tonight.
Since upgrading I have only seen this issue once and it was fixed by pressing control and refresh.
Out of the thousands of users we have here it appears there are only 3 or 4 having the issue, which has me believing it is something on their systems. If you are running ad block, try turning that off as I have read it blocks some feature of this new software. (and your all pub members anyways so you see no ads)