Danny D wrote:

Cooking oil will help. Don't actually cook the glass,tho.

Personally, I gave up on the oil idea as I didn't find the
vegetable oil anywhere nearly as effective as the petroleum
distillates (gasoline was the best) in instantly dissolving
the gummy deposits on the plastic gummy vitamin jars.

Try Goo Gone or Goof Off or similar product made especially for
dissolving gummy things.