I've never used a gas oven, but on an old electric oven with exposed elements we would lift it up and put foil underneath to catch the drippings. On newer toaster ovens I've seen that they have moved the heating element so that it is now hidden under the lower surface of the oven.
On these ovens, aluminum foil can burn to the surface and damage the porcelain surface. I have had two ovens damaged this way, one ours and one in a rental. I suspect it could damage a gas oven as well, but don't have any personal experience with that. Use a self-cleaning feature or some oven cleaner to remove drippings, but don't use foil.
