Custom HTML/JavaScript in Custom Field Descriptions no longer working in Jira 8.7

Problem

Upgraded to Jira 8.7 and behaviours not working correctly on Select lists, or seeing random code in the fields description?

If you have behaviours that are not working correctly on "Select List" custom fields and you have configured these fields to use custom HTML/JavaScript in the Custom Fields Description please check the below:

Solution

Jira 8.7 automatically disables the feature labelled as "Enable HTML in custom field descriptions and list item values" so if your custom HTML or JavaScript now just shows as text where your fields description should show and your custom code is not being executed you will have to re-enable that feature or load your custom JavaScript in a different way such as our web resources feature.

Atlassian bug reference:
https://jira.atlassian.com/browse/JRASERVER-38866?src=confmacro

The bug is referenced in the release notes for Jira 8.7 here https://confluence.atlassian.com/jirasoftware/jira-software-8-7-x-release-notes-990550432.html