Define the following field style in any instance release.
Field name: Opened
When you view the Incident list you will see that for this 'Date Time' field it is then displayed on two lines instead of one like for other fields, as shown in the following screenshot:
This is reproducible in all releases.
Problem PRB658846 was raised for this behaviour, however it was closed by our Development team as "Won't Fix" for the following reason:
"We have no plan to address in one of the foreseeable upcoming releases, therefore applying our current policy which is to Close with a resolution code of Won't Fix"