Label custom field does not show in the color by settings

Issue Summary

I've added two custom fields in the plan (Configure > Custom fields) but when I want to customize my view and sort via these custom fields, only the select list custom field is appearing. The Label custom field is not available.

Steps to Reproduce

1. Create two custom fields in Jira. One label type and another one is select list.
2. Make sure that some issues in the plan have value for these custom fields
3. Add these custom fields in the plan (Configure > Custom fields)
   custom label field
   
4. Click on View Settings > Color by

Expected Results

The custom label field should be available.

Actual Results

Only the select list custom field shows up. The custom label field is not.

Workaround

Currently, there is no known workaround for this behaviour. A workaround will be added here when available