List variables in schedules should not show the same properties twice

Current Situation

• A workflow W1 defines a list variable L1.
• The list variable L1 has the property P1.
• Workflow W1 is assigned the schedule S1.
• Schedule S1 defines 2 entries for the list variable L1.
• When a second property P2 is added to the list variable L1 in workflow W1 then the property displayed twice in schedule S1.

Desired Behavior

When a property P2 is added to a list variable L1 in workflow W1 then the property P2 should be displayed just once for each entry in schedule S1.