I've found that select2 have an error on Metabox.io main plugin and date inputs didn't work, so i replace it with the new .js downloaded directly from Select2 page, and it is working fine.
I've just updated select2 to the latest stable version 4.0.5. Would you mind give me more details on the bug, so I can check it to prevent it from happening in the future? I've just checked with the select_advance and date field and don't see any problem.
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