An automatic table of contents element is now included in Oxygen version 3.7. Previously, I had to find a plugin to easily generate a table of contents or it had to be coded manually. This is a composite elements so it can be updated on the fly from the Oxygen dev team. We also take this a step further with the MDL Menu component from the Material Design Lite for Oxygen design set to make the menu collapsible.
Learn more about my Oxygen Builder course and included MDL design set here: https://jonathanjernigan.com/ultimate-oxygen-course/
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