Missing Icon for exiting part editing in assembly

When I edit a part within an assembly, I used to be able to click on an  icon in the top right hand corner of the screen to return to the edit assembly mode.  Now the icon flashes and then disappears.  I exit the part edit mode and return to assembly edit mode by right clicking and then selecting "Edit Assembly".  Anyone else having this problem or found a solution?

SolidworksAssemblies