To access settings for the side navigation, go to:
Structure > Block layout > Block types

Then select Illinois Framework Theme

Body
- Scroll down to the heading Sidebar First, and select "Configure" to the far right of Main navigation as shown below.

- Under Configure block, scroll down to "Number of levels to display" select "Unlimited"

- Under Advanced options, scroll down to "Use as title" select "Active trail's root title"

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