Reported in https://www.drupal.org/node/2271117#comment-8818203

The patch from that comment fixes media_wysiwyg so that you can have media image inserting working even if you have multiple text areas.

Cross referencing the issue here because the issue came up for me while working on a Panopoly based site.

If you find that you can't edit a component that has multiple textareas after you added an image to one of them. This is wehil.