Fotoartist wrote:
One workaround to an "embedded" image is to make a "screen grab" to recreate the file. Screen grabs on Mac are Option, Command, 3 for the whole screen, or Option, Command, 4 for a cursor to swipe just what you want on the screen.
On my MacBook Pro using High Sierra (just released OS) that would be shift+command+3 or 4 for whole screen or selection.