What is the test for content-based regulations in the context of the First Amendment?

Hence, "The First Amendment generally prevents government from proscribing speech [citation], or even expressive conduct [citation], because of disapproval of the ideas expressed. Content-based regulations are presumptively invalid." (R.A.V. v. City of St. Paul, Minnesota (1992) 505 U.S. 377, ----, 112 S.Ct. 2538, 2542, 120 L.Ed.2d 305 citations omitted; Texas v. Johnson, supra, 491 U.S. at p. 414, 109 S.Ct. at p. 2545.)