There are a few ways to resize a layer mask in Photoshop. The easiest way is to use the layer mask tools on the left side of the screen. These tools allow you to resize the mask by dragging it left or right, or up and down. Another way to resize a layer mask is to use the Edit menu and select Resize Mask. This will open a dialog box where you can choose how much space to give the new mask, as well as how wide or narrow it should be.
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