I have created a lot of processes and tried linking them together. The linked expansion
icon is not showing up in the linked processes for all new linked processes except those created approximately 3 months ago. All config settings are set to display for all users.

Further investigations have shown that the promaster user didn’t have a role attached to their user account but even when this was rectified the issue remains.
We’ve since tested and discovered that the Linked Process Expanding icon now shows when the process has been approved. It’s most useful though for the approver to see the linked processes during the approval process.