Perhaps I missed it but I don't see any way to enable the sections everywhere. I've created a new experimental dev store with Unite 2019 selected. It comes with a Debut and Dev Preview theme. Both of these themes appear to be using the old snippets-style paradigm.
Are there steps I need to perform to enable sections everywhere?
Solved! Go to the solution
So you can add the new directories to a pre-existing theme, and upload it this to a developer preview store and test out the new content model and section schema format, on a code level. However, you won't be able to work with sections on all pages until the new UI is launched later this year. Keep in mind too, that currently the new file directory is only compatible with developer preview stores.
Hope this helps Jon!
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