∀ {A : Type u_1} {B : Type u_2} [inst : CommRing A] [inst_1 : CommRing B] [inst_2 : Algebra A B] {G : Type u_3}
  [inst_3 : Group G] [inst_4 : MulSemiringAction G B] [inst_5 : SMulCommClass G A B] [inst_6 : TopologicalSpace G]
  (P : Ideal A) (Q : Ideal B) [Q.LiesOver P] (N : OpenNormalSubgroup G),
  (Ideal.under (↥(FixedPoints.subalgebra A B ↥↑N.toOpenSubgroup)) Q).LiesOver P