Yeah using it for repeater wysiwyg provides a challenge. I think that Elliot created the wysiwyg field before wp_editor() became available as I can’t see that he’s using it in core. Or perhaps there’s another reason.
In any case looking through the code it does not seem to be any available undocumented hooks for working with the classnames.
I will assign @elliot to this topic and perhaps he has some more feedback.
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