Hi Bill,
Following trick works for me:
1. Add a model action onto the model that the field editor is looking at
2. In the model action, have the initiating event be row in model is updated, and specifically the picklist field
3. In the model action, the first action is a branch where the formula is {{PicklistFieldName}} == “ValueThatTriggersPopup”
4. Under the branch-if-true actions (hit the red plus next to Branch), you can include the popup
Thanks
