The following is an embedded media streamfield. Note that Google’s oEmbed provider won’t pass the rel=0 attribute
The following is a media embed inside a richtext streamfield (same problem)
The following is an iframe inside a raw HTML field. Not ideal! It isn’t appropriately responsive and using this module is a security risk.
the following is in an iframe streamfield. It seems(?) like we can pass through the rel=0 parameter. This allows us to control the styling (so it’s mobile-responsive), and this is more secure. But note that you have to specify native width and height to get it work OK.