Problem/Motivation
In #2994696-218: Render embedded media items in CKEditor, we added a new asset library to the Media module (and therefore, to Stable) -- media/media_embed. It contains some minimalistic default styling for embedded media items -- more specifically, for the error that appears in place of an embedded media item, should something go wrong during rendering (or live preview in CKEditor).
Adding a new asset library seemed to us like the easiest and most "traditional" thing to do in that issue, and @webchick agreed with us. However, some comments from @lauriii in the issue suggest that we might want to roll back some of the styling opinions added by that library, or at least move them to Classy.
Proposed resolution
Figure out what, if anything, from this new library should be refactored or copied/moved into Classy.
Remaining tasks
TBD
User interface changes
TBD
API changes
TBD
Data model changes
TBD
Release notes snippet
TBD