I have an option on post edit screen that can change it to full-width. Unfortunately, $content_width still follows the standard one with sidebar 780px (without saving the post or a whole refresh).
I have figured out the method responsible for getting this data. It's action wp.media.model.Query.sync() method in js/media-models: https://github.com/WordPress/WordPress/blob/master/wp-includes/js/media-models.js#L1225
Anyone knows how to pass custom post data here (layout=full) with this AJAX request? (I will filter on that AJAX request to set $content_width=1170).
