When making any sort of change to an image, from overlaying a gradient, to resizing a box shape, to editing the levels, etc. Photoshop will not immediately reflect the new action done to the image. It will appear exactly as it did before I made the change UNTIL I either zoom in/out or make another change (in which case it shows the prior change, but not the new one until I do the same thing again - rinse/repeat). This does not happen every time I open Photoshop, sometimes it works fine and sometimes it decides to do it. If I quit Photoshop and reopen, it does not fix the problem. If I restart the computer, it may fix it or it may decide to do it that time as well. This is a very very annoying bug that seems to plague me fairly often in Photoshop ever since CC 2018 (which has been very buggy overall). \\ I have deleted all Photoshop preference files, uninstalled the app, reinstalled it and restarted the computer. Does not prevent it from happening. Photoshop 19.1 Mac osX 10.13.2 iMac 5k
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