After creating the Assistant window in Glade, I was presented with a window with three labels, each of which is a page.
But how to add another page and its corresponding widget?
Set the number of pages you need in the assistant properties window. The number of pages must be greater than the number of widgets of child pages added to the assistant window.
Reorder existing child widgets of child pages by changing their property Positionon the Packaging tab. You want the first position (position 0) to be empty. The easiest way to do this is to increase each child position by one, starting with the last child.
Position
assistant-action-area . 0, .
assistant-action-area
.
, .