diff --git a/clang/lib/Sema/TreeTransform.h b/clang/lib/Sema/TreeTransform.h
index dee335b526991..6ef2eec09ec02 100644
--- a/clang/lib/Sema/TreeTransform.h
+++ b/clang/lib/Sema/TreeTransform.h
@@ -7216,9 +7216,30 @@ TreeTransform<Derived>::TransformElaboratedType(TypeLocBuilder &TLB,
       return QualType();
   }
 
-  QualType NamedT = getDerived().TransformType(TLB, TL.getNamedTypeLoc());
-  if (NamedT.isNull())
-    return QualType();
+  QualType NamedT;
+  if (SemaRef.getLangOpts().CPlusPlus20 && QualifierLoc &&
+      isa<TemplateSpecializationType>(TL.getNamedTypeLoc().getType())) {
+    TemplateSpecializationTypeLoc SpecTL =
+        TL.getNamedTypeLoc().castAs<TemplateSpecializationTypeLoc>();
+    const TemplateSpecializationType *TST =
+        SpecTL.getType()->castAs<TemplateSpecializationType>();
+    CXXScopeSpec SS;
+    SS.Adopt(QualifierLoc);
+    if (TemplateDecl *TD = TST->getTemplateName().getAsTemplateDecl()) {
+      TemplateName InstName = getDerived().RebuildTemplateName(
+          SS, TL.getTemplateKeywordLoc(), *TD->getIdentifier(),
+          TL.getNamedTypeLoc().getBeginLoc(), /*ObjectType=*/QualType(),
+          /*FirstQualifierInScope=*/nullptr, /*AllowInjectedClassName=*/false);
+      if (InstName.isNull())
+        return QualType();
+      NamedT = TransformTemplateSpecializationType(TLB, SpecTL, InstName);
+    }
+  }
+  if (NamedT.isNull()) {
+    NamedT = getDerived().TransformType(TLB, TL.getNamedTypeLoc());
+    if (NamedT.isNull())
+      return QualType();
+  }
 
   // C++0x [dcl.type.elab]p2:
   //   If the identifier resolves to a typedef-name or the simple-template-id
diff --git a/clang/test/SemaCXX/PR91677.cpp b/clang/test/SemaCXX/PR91677.cpp
new file mode 100644
index 0000000000000..cc8db60a438ea
--- /dev/null
+++ b/clang/test/SemaCXX/PR91677.cpp
@@ -0,0 +1,14 @@
+// RUN: %clang_cc1 -verify -std=c++20 -fsyntax-only %s
+// expected-no-diagnostics
+
+template <typename> struct t1 {
+  template <typename>
+  struct t2 {};
+};
+
+template <typename T>
+t1<T>::template t2<T> f1();
+
+void f2() {
+  f1<bool>();
+}
diff --git a/clang/test/SemaTemplate/typename-specifier-3.cpp b/clang/test/SemaTemplate/typename-specifier-3.cpp
index 714830f0032d2..a62a1fc5ab39c 100644
--- a/clang/test/SemaTemplate/typename-specifier-3.cpp
+++ b/clang/test/SemaTemplate/typename-specifier-3.cpp
@@ -28,16 +28,17 @@ namespace PR12884_original {
       typedef int arg;
     };
     struct C {
-      typedef B::X<typename B::arg> x; // precxx17-warning{{missing 'typename' prior to dependent type name B::X; implicit 'typename' is a C++20 extension}}
+      typedef B::X<typename B::arg> x; // precxx17-warning{{missing 'typename' prior to dependent type name B::X; implicit 'typename' is a C++20 extension}} \
+                                       cxx17-error{{typename specifier refers to non-type member 'arg' in 'PR12884_original::A<int>::B'}}
     };
   };
 
   template <> struct A<int>::B {
     template <int N> struct X {};
-    static const int arg = 0;
+    static const int arg = 0; // cxx17-note{{referenced member 'arg' is declared here}}
   };
 
-  A<int>::C::x a;
+  A<int>::C::x a; // cxx17-note{{in instantiation of member class 'PR12884_original::A<int>::C' requested here}}
 }
 namespace PR12884_half_fixed {
   template <typename T> struct A {