The shift key is being weird when drawing freehand. What still works is holding shift first and just drawing straight (using any brush/pencil). And using Shift to click, then click a straight line. But if you're freehand drawing and THEN hold down the Shift to make a straight horizontal or vertical line - things get wacky. It works once- but if you let up and then try it again, it jumps around to another location on the page and then draws a random straight line. Does this repeatably. It's like using an Etch-a-Sketch.
This is NEW with the most recent update of Photoshop, and not welcome. Using MacOS 10.13.6
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