Allow Optional Workflow Output Parameters [C OG]

Previous to VidiFlow 20.1, all workflow output parameters were always handled as mandatory output parameters. Meaning that those parameters should have a value assigned inside a workflow. This especially caused problems in usage of sub workflows.
You can activate the option "Optional" for each workflow output parameter. Then you will have to provide a default value for that parameter.
If the parameter does not get a value assigned inside the workflow, it will keep the default value.