How do I enable Lessons subpage navigation in the Tool Menu?
Go to Site Info.
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Select the Site Info tool from the Tool Menu of your site.
Scroll down and click Continue.
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You may now click on the top level Lessons page in the Tool Menu to display its subpages as links in the menu.
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The subpages will display.
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Note: Only one level of subpage will be added to the menu, regardless of how many additional pages are nested within those subpages.