My organization just upgraded from Portal 10.4.1 two days ago and I'm seeing a difference in how related records are accessed in a web map vs a WAB app.
In the web map I see this in the popup where it is one click on the Show Related Records link to open the table.

In the WAB I get this:

I have to click on the arrow first to get this:

Then I click on the 3 dots to show the attribute table. I can see how this new popup provides other functionality but in a way it makes it more complicated and less efficient (2 clicks instead of 1). Is there way to make the WAB behave like the web map? I haven't found any documentation on this yet.