The best way I've found is using your fingers only, pry evenly around the edges. The sharp edge of a tool like a screwdriver can create too much point pressure resulting in breakage. I have a broad, smooth edged pry tool that I sometimes use though. Cold will crack 'em though, so you might want to park in the sun for a while.
That's a cool idea. I never thought that these fingers will be enough to move around the edges smoothly. I prefer tools like screwdriver but what you said really makes sense.
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