Oh god, this gave me a minor heart attack. We are using over 20 ACF fields for 150+ sites. I thought it was completely out of the WordPress ecosystem. I am glad they have the zip download and continuing auto updates.
EDIT: I confirm our ACF plugins on sites are all switched to secure custom fields. This is so shady, it broke our snippets because we are using prepend and append texts to wrap our field values. Now they are all broken and we have to update all our sites (also our client's sites). Let's see what comes next...
EDIT2: There goes my Sunday. I received our first ticket regarding broken homepage widgets. I have to sit down and update every site one by one. Thank you Matt Mullenweg for ruining my Sunday plans.
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