I3 usage

Concepts

Containter Management

Split-Vertical ($mod-v), or Stack-Vertical($mod-a) will create a container above your window.
New windows created while this container's windows are focused will be arranged as configured.

You may also select the parent container and change how it's stack will work.

Example

1. you have 2x windows you want to stack vertically

$mod+a  # select parent container
$mod+u  # stack vertically

2. you want to create a 3rd window, outside of the stack in a vert split

$mod+a            # select parent container
$mod+v            # split horizontally
$mod+shift+enter  # create 3rd window

3. continuing to use layout

# new windows from container selections will be created inside container
# new windows created from the vert split will be stacked that way
# you can use this to have multiple independently stacked vert-splits