Gutenberg: Blocks: Arrow up from quote citation empty newline skips to quoted text

[aduth]

Issue Overview

When a quote block citation includes line breaks, attempting to press Arrow Up from any of a blank new line of the citation will result in the caret being moved to the quoted text, rather than the line preceding it.

Steps to Reproduce (for bugs)

1. Insert quote block
2. Enter some text
3. Arrow Down into citation field
4. Insert a line of text
5. Press Enter
6. Press Arrow Up

Expected Behavior

Caret is moved to moved to the first line of the citation.

Current Behavior

Caret jumps to quoted text.

Possible Solution

Likely something going on with edge detection in WritingFlow.

Video

[iandunn]

Related https://github.com/WordPress/gutenberg/issues/7838

[aduth]

I'm having trouble repeating the original steps here, due to as best I can tell a bug in TinyMCE, reported at https://github.com/tinymce/tinymce/issues/4488.