That’s as may be, but I rarely use portrait mode. All the mags I read, and sites I look at, work well in Landscape mode, including the old Steinberg forums.
The Nexus’s case allows it to be easily propped up in landscape mode, which can not be said for Portrait mode.
It is the ‘Search’ boxes that are causing the problem. As soon as the tablet detects an active search box it opens the virtual keyboard on top of everything, as you saw.
I still don’t see the point of having the Search boxes - there are never going to be dozens or hundreds of entries in these forum lists. If they can be made optional - problem solved.