iOS iPhone display becomes half blank--Bug

Hardware: iPhone 12 Pro
iOS version: 15.6
Scrivener version: 1.2.2

To reproduce:

  1. Place your iPhone in landscape mode.
  2. Open Scrivener.
  3. In some Scrivener project (like the Tutorial) open a nice long document (like Key Concepts.) The document must have more than one screenful of text.
  4. Tap the screen to start editing said document. Make sure the cursor is blinking.
  5. Flip your iPhone into portrait mode.

Expected result:
The document displays normally in portrait mode, with the cursor blinking ready to accept text input.

Observed result:
The document is no longer in edit mode, and the lower half of the document area is blank, like this:

All the text is still there and can be scrolled, but display is limited to the top portion of the document pane. Once edit mode is entered by tapping somewhere in the text, the text display returns to normal.

I have seen this. macOS, too.