DTPO 3.0.3 and scripting

Did something change is 3.0.3, as none of the scripts to transfer a Group to (Things, Reminders, OmniFocus) as a reminder work anymore i.e. if I select a group and run the script, I received the message “Please select a document or group, then try again.”, and I validated that thisSelection variable is indeed empty.

However if a select a document within a Group, the scripts are still working…

No, nothing has changed in this regard.
I am surmising you are making a selection in the Navigate sidebar, which doesn’t report selections. Try selecting the group in the item list and see if the issue recurs.

Indeed. But that is not a new behavior? I always only work with the sidebar for Group navigation and the main list screen for documents…

The selection AppleScript property always used only the selection of the main view like in version 2.