TinyMCE conflict with MailPoet

Have you checked my post ? https://www.ads-software.com/support/topic/tinymce-buttons-lost-when-using-with-syntaxhighlighter-tinymce-button-in-35
It might be the same issue.

Removing the call to wp_tiny_mce() fixed the issue and I didn’t encountered any other issue so far (I still don’t know what this call does though…)