"Insert/Edit image" button is missing from CiviMail's WYSIWYG HTML message editor

The "Insert/Edit image" button is missing from CiviMail's WYSIWYG HTML message editor, which exists in the 1.9 version.

Under 1.9, this button would sometimes convert static links to relative links. This should also be reviewed.

Also, I'm not clear on the purpose of the huge drop-down that fills the second row of the toolbar under 2.0.