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People thing that this is a good way to stop the spills, well it may do but it also can cause damage to the enamel of the grill pan and more seriously the bottom of the oven. The reason for this is that the foil reflects the heat back onto the base of the oven and the heat intensifies and gets to a really high temperature and hence causes the damage.
I would recommend an oven liner which is a purpose designed and made from PTFE with a teflon coating from a kitchen supply company such as lakeland. This will help protect the bottom of the oven from drips and help you to keep the oven clean.