Hi. Based on Orbeon 2018.01 CE:
We have an issue using the "appearance="tree tree-plus-minus"" onder xf:select1 when it is in a dialog. I've added a reproduction form here.
The phenomenon: the dialog will continue to show and work with the tree it has in its instance when it opened the very first time after the form was loaded, regardless of changes in that instance, for as long as you work with the same form.
Any changes in the instance under xf:select1/xf:itemset are not evaluated for display/logic. The xforms-inspector however has exactly what you expect in the instance.
Hope you can issue an update for this tricky issue.
Best regards
Alexander Henket