I'm following the guide as you linked but it not showing up. Can you post your .content.xml file? Or a link to the source repo for that screenshot? Thanks!
Following this guide, I'm trying to enable the style system for the Core Page Component (v2) in edit mode (Page Properties) for a use I have. <?xml version="1.0" encoding="UTF-8"?>
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~ Copyright 2017 Adobe
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~ Licen...