Image upload subfield broken with 3.1.8 and later releases

Problem/Motivation

On a Drupal 11.1.7 project, I'm using custom_field 3.1.7 with an image upload subfield. Perfect.
Updating custom_field to 3.1.8 (and updating the DB, caches cleared), the subfield output is empty.
No error in console or log, just an empty field wrapper.
Updating custom_field 3.1.9: same issue, no output.

I've tried, without success:
- adding a new image subfield to my existing custom field (using the new drush addcolumn command),
- deleting the custom field and creating a new one with an image subfield
- doing all the same on a fresh D11 install

Reverting to custom_field 3.1.7 brings back the image output.
The only workaround I found is using the custom template widget in the view mode and rebuild the <img> tag with the image url as [node:field_csutomfield:image:thumbnail]
or using a media subfield but I'd like to keep my existing custom field.