This issue has been migrated a new MRTK repository, and the status of this issue will now be tracked at the following location:
Overview
The tabs in the main canvas of CanvasExample.scene don't work.

Repro
- Open CanvasExample.scene
- Click a "tab" in the main canvas
- Nothing changes in the main canvas
Excepted
The main canvas to change in some way when selecting a tab, for example images to change.