4.11 Supply Collection Data ↑
4.11.3 Supply Left Side Navigation
The navleft command can be used to place some sort of navigational elements at the top of every page, but appearing on the left side rather than the Supply Page Navigation stuff that normally appears to the right.
If supplied, this element can be used to replace the upwards navigation normally appearing to the left when in Streamlined Reading mode.
Here’s an example.
{:navleft}