Android: Screen reader accessibility: Navigation by lines doesn't navigate by lines

Describe the issue

On Android, TalkBack's "navigate by line" feature has trouble when working with a CodeMirror editor. In particular, when navigating by lines,

• Using TalkBack's next/previous line navigation, focus often navigates to the next or previous region with syntax highlighting, rather than the next/previous line.
  • See the attached screen recording.
• The content read by TalkBack often doesn't match the content near the cursor.

Screen recording

https://github.com/user-attachments/assets/d269bc0c-e487-42d3-bac3-6b84664cb2b1

The above screen recording shows:

• TalkBack reads text from near the start of the document when navigating by line near the end of the document.
• Navigation by line moves the cursor less than a full line.
• Navigation by line reads content not near the cursor.

Browser and platform

Chrome 135.0.7049.111 / Android 13

Reproduction link

https://codemirror.net/try/#c=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