I agree that the baking soda and vinegar solution is the best possible choice here. The baking soda is a base and the vinegar is an acid, and when you mix them together they create lots of foam, which can clean practically everything. The only thing you need to be careful about is to not scratch the surface of the oven glass. But since all the oven glass is strong and fireproof, this shouldn't be an issue. According to professional oven repairs and maintenance specialists, if you leave the solution to work long enough, you won't even have to scrub. All you'll need to do is wipe the glass in the end.