Steps to reproduce:

1. Enter a caption with a short text string
2. Enter another caption with a long text string that exceeds the character/byte limit. Notice how the "Publish" button becomes disabled.
3. Delete the caption in step 2.
4. Publish button does not become enabled again.

Expected/desired behavior: when all offending text boxes are no longer present, re-enable the publish button.

See GIF below for an example of the bug.