I’ve seem to fixed the issue by replacing the post object (custom post type) with a normal repeater.
I think it’s still possible to use post objects in combination with the flexible content field, but for now my problem has been solved.
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Accordions are a great way to group related information while allowing users to interactively show and hide content. In this video, Damon Cook goes in-depth on how to create an accessible accordion block using ACF PRO’s Repeater field.https://t.co/RXT0g25akN