Relationship field performance

I got it. Thanks for the clarification.

I'm afraid there's no way to detect a field is closed or open, especially in different context (classic or block editor).

At the moment, the queries when page loads are minimal as they query only selected items. I don't think that's a performance bottle neck.

Hello, can you update the link?
I got 404 for this: https://github.com/wpmetabox/meta-box/tree/ajax-post

also when you will merge all this to master and realese the new version including all this improvements?