Making a Custom Field mandatory in Jira

[Rahul R]

I have a custom field called "Root Cause" which is associated with Issue Type "Bug". Is there a way I can make that a "required field" when I try to resolve/close an issue type "Bug"?

[MJ]

This requirement can be set up uising a validator in the Workflow used by the Bug Issue-type.
First you will need to install the JIRA Suite Utilities plugin. This is a free plugin available on the Atlassian Marketplace.

This plugin, among other things, adds several workflow options. One of them is the Fields Required validator. I believe this validator priveds you the functionality you are looking for.