Add Columns doesn't have Output checkbox

Edit 2: The problem is there’s no Output checkbox on Add Columns

Original post below, not relevant to the problem

Wappler 4.7.1
MacOS

The server-side step Add Columns is not visible in the Data Binding Picker when such is inside a Library function and called through Exec. If I add an Exec step and call the Library function, I can only see the database query but not the Add Column variable

Library

• MyTest: Database query + Add Column

API

• Exec to Library/MyTest
• Set Response to variable Exec/Library/MyTest/AddColumn (doesn’t exist)

Edit: Seems not just the UI is affected, it also gives null
Edit 2: The problem is there’s no Output checkbox on Add Columns