Custom field wiki style renderer has User Mention Button which custom field doesn't support mention in the first place

Summary

Custom Field Wiki Style Renderer Has User Mention Button Which Custom Field Doesn't Support Mention In The First Place

Step to reproduce:

• Create a custom field with Text Field (multi-line)
• Assign to any screen
• Navigate to Field Configuration page (or press "gg" and search for Field Configuration)
• Click on Configure button on any field configuration that contained your custom field.
• Navigate to your custom field and click on "Renderers" button.
• Choose Wiki Style Renderer
• The custom field will look like the below image:

In conclusion, User Mention button does not belong in that custom field since custom field does not support mention. There is a feature request for this case.