Sets a side image for @page.
This image used to be displayed in the side area of the assistant when @page is the current page.
a page of @assistant
the new side image @page
Deprecated: Since GTK+ 3.2, sidebar images are not shown anymore.
2.10
See Implementation
Sets a side image for @page.
This image used to be displayed in the side area of the assistant when @page is the current page.