The Gutenberg module is hard coded to convert the first compatible text field on a content type to use the gutenberg format. This means on a content type with multiple long text fields one is always converted to the gutenberg format but not necessarily the correct one. There is currently no way to choose which field should be a gutenberg field.
Create multiple long text fields on a content type. Enable gutenberg on the content type. Observe the first field is made into a gutenberg editor experience whereas the rest are placed in the 'more settings' area of the node form.
Add an option/config to the content type form to allow the field to be chosen. I imagine this may cause some issues if a field is chosen and then later deleted but an appropriate error could be displayed.
Add an option to choose from available long text fields.
Needs review
2.0
Code
The change is currently missing an automated test that fails when run with the original code, and succeeds when the bug has been fixed.
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It's likely this issue predates Contrib.social: some issue and comment data are missing.
Let's add some tests to this before merging.
Also, if someone could create a merge request with the patch it's so much easier to review, comment and commit