What if you’re working with the Brush or Gradient tools on a multi-layered image and press the Option (PC: Alt) key to sample a color, but the color won’t change to the one on which you clicked? (“Photoshop is buggy!” I hear you scream.) Just choose the Eyedropper tool (I) and make sure the Sample drop-down menu in the Options Bar at the top is set to All Layers. Even though you can’t always see the Eyedropper preferences, they’re still active.
This tip previously appeared in Colin Smith’s Photoshop Tips column, in the May, 2019 issue of Photoshop User magazine.