I recall in the past there were issues with certain controls containing other controls, especially when it came to these three.
Is this still and issue (2019r1)?
I have a PagePanel, that has a Groupbox on each pane, and at least one of those groupboxes contains a TabPanel
each groupbox will have other controls (checkboxes, radiobuttons, textedit etc)… and the Tabpanel(s) will contain the same
If this is still a fragile structure , I would rather design around it now, then fall on my face and have to rework it all later