Header Row for Subtask List in Issue Detail View

Activating a header row for the subtask list in the Issue Detail View has been supported in the past by editing view_subtaskissues.jsp. See How to Activate Header Row for Subtask List in Issue Detail View | Atlassian Support | Atlassian Documentation
However, view_subtaskissues.jsp no longer exists. I’m looking to enable the sub-task headers in JIRA 7.5.

poking again here - anyone know how to enable sub-task headers?