Grease pencil onion skin not showing in draw mode 2.81 but works fine in 2.80 - Blender Stack Exchange
animation - Onion skin wont show unless I draw on the frame, and only shows the lines directly around it from previous frames and won't lower onion skin's opacity - Blender Stack
Grease pencil onion skin transparency is messed up/becoming white - Technical Support - Blender Artists Community
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