your approach is actually not that hard to do as ACF has form tag that you can use in the front end. the preview before save might be a bit trickier with this approach but i am sure we could figure something out.
my approach of inline editing was meant for tweaking content and fixing typos rather than creating new sections and i wanted it to be super intuitive without extra ui elements.I have an idea how to make repeaters work, which would allow to use flexible content and all that, just dont have time for that at the moment.
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