Issue: Picking colors outside the After Effects interface switches the application rather than picks a color.
In After Effects 2014.1 (13.1), and later, on Mac OS, clicking with the mouse outside the After Effects user interface does not sample the color, it switches you to the other application.
When you use the After Effects eyedropper tool and want to sample a color outside the After Effects user interface, press Return or Enter instead of clicking the mouse button. The operating system won’t switch to the application you sampled the color from, and you won’t have to click back into After Effects to continue working.
Pressing Return or Enter works on both Windows and Mac OS, whether you’re sampling a color inside or outside After Effects.