Reproduces on Android v2.12 build 501 and v2.13 build 503

Steps:

1. Paste a 16383 character message into a channel (use sample file attached)
2. Long press on the posted message and select “Edit”
3. Scroll down to the bottom and insert one character
4. Observed at top of the screen “Message exceeds the character limit 16384/16383”

Observed:
Once the error message has appeared at the top of the screen, you’re not able to scroll down to the end of the post to edit/remove characters

Expected:
Can scroll down to the end of the post to edit/remove characters

16383_characters.txt

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JIRA: https://mattermost.atlassian.net/browse/MM-56679