Summary

If you create a custom field and set it as required in the field configuration, older created issues (before this setup) will be affected if the field is not populated.
It won't be possible to Share the request trough the customer portal, it will be only possible to do so trough the issue page in the project.

Environment

Jira Service Desk Cloud.

Steps to Reproduce

1. Create a custom field (tested with Select list (single choice));
2. Set it as required in the field configuration;
3. Go to older issues that use the same field configuration (related issue type) and click to show them in the customer portal;
4. Try to share with anyone:

• After you search a user, nothing happens when you click on Share, but if you use the inspect feature in your browser you will be able to see a error being triggered (click on the link from the 500 error that appears -> click on the share file):

  {"errors":[{"errorMessage":"Failed to validate request participants field, errors: "}],"reasonKey":"sd.request.participants.error.field.validate.failed","reasonCode":"500"}

Expected Results

After hitting the Share button, a participant should be added.

Actual Results

Nothing happens.

Workaround

Populating the custom field in older issues (that are being affected) gets it back to working.