This article is from the PEZ candy and PEZ dispensers FAQ, by sharpe@dg-rtp.dg.com (Chris Sharpe) with numerous contributions by others.
Use a razor blade or Exacto knife to remove the plastic bubble from
the card. Cut away as much as possible without damaging the card.
Remove the candy and dispenser. Place the card with the remaining
glued plastic in the microwave. Turn the microwave on high for 1 to 2
minutes (you'll have to experiment with your microwave to determine
what time works best). Make sure the plastic is very loose before you
attempt to remove it. It won't fall off by itself, but shouldn't
require pulling. Be sure to remove the plastic before the glue cools
and begins to set.
 
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