diff --git a/internal/checker/types.go b/internal/checker/types.go
index ae842ea0cd..2e5ea1f81d 100644
--- a/internal/checker/types.go
+++ b/internal/checker/types.go
@@ -427,18 +427,18 @@ const (
 	TypeFlagsUniqueESSymbol  TypeFlags = 1 << 14 // unique symbol
 	TypeFlagsEnumLiteral     TypeFlags = 1 << 15 // Always combined with StringLiteral, NumberLiteral, or Union
 	TypeFlagsEnum            TypeFlags = 1 << 16 // Numeric computed enum member value (must be right after EnumLiteral, see getSortOrderFlags)
-	TypeFlagsNever           TypeFlags = 1 << 17 // Never type
-	TypeFlagsTypeParameter   TypeFlags = 1 << 18 // Type parameter
-	TypeFlagsObject          TypeFlags = 1 << 19 // Object type
-	TypeFlagsUnion           TypeFlags = 1 << 20 // Union (T | U)
-	TypeFlagsIntersection    TypeFlags = 1 << 21 // Intersection (T & U)
-	TypeFlagsIndex           TypeFlags = 1 << 22 // keyof T
-	TypeFlagsIndexedAccess   TypeFlags = 1 << 23 // T[K]
-	TypeFlagsConditional     TypeFlags = 1 << 24 // T extends U ? X : Y
-	TypeFlagsSubstitution    TypeFlags = 1 << 25 // Type parameter substitution
-	TypeFlagsNonPrimitive    TypeFlags = 1 << 26 // intrinsic object type
-	TypeFlagsTemplateLiteral TypeFlags = 1 << 27 // Template literal type
-	TypeFlagsStringMapping   TypeFlags = 1 << 28 // Uppercase/Lowercase type
+	TypeFlagsNonPrimitive    TypeFlags = 1 << 17 // intrinsic object type
+	TypeFlagsNever           TypeFlags = 1 << 18 // Never type
+	TypeFlagsTypeParameter   TypeFlags = 1 << 19 // Type parameter
+	TypeFlagsObject          TypeFlags = 1 << 20 // Object type
+	TypeFlagsIndex           TypeFlags = 1 << 21 // keyof T
+	TypeFlagsIndexedAccess   TypeFlags = 1 << 22 // T[K]
+	TypeFlagsConditional     TypeFlags = 1 << 23 // T extends U ? X : Y
+	TypeFlagsSubstitution    TypeFlags = 1 << 24 // Type parameter substitution
+	TypeFlagsTemplateLiteral TypeFlags = 1 << 25 // Template literal type
+	TypeFlagsStringMapping   TypeFlags = 1 << 26 // Uppercase/Lowercase type
+	TypeFlagsUnion           TypeFlags = 1 << 27 // Union (T | U)
+	TypeFlagsIntersection    TypeFlags = 1 << 28 // Intersection (T & U)
 	TypeFlagsReserved1       TypeFlags = 1 << 29 // Used by union/intersection type construction
 	TypeFlagsReserved2       TypeFlags = 1 << 30 // Used by union/intersection type construction
 	TypeFlagsReserved3       TypeFlags = 1 << 31
diff --git a/testdata/baselines/reference/compiler/objectSubtypeReduction.symbols b/testdata/baselines/reference/compiler/objectSubtypeReduction.symbols
new file mode 100644
index 0000000000..89728315e0
--- /dev/null
+++ b/testdata/baselines/reference/compiler/objectSubtypeReduction.symbols
@@ -0,0 +1,26 @@
+//// [tests/cases/compiler/objectSubtypeReduction.ts] ////
+
+=== objectSubtypeReduction.ts ===
+// https://github.com/microsoft/typescript-go/issues/1164
+
+function foo(x?: object) {
+>foo : Symbol(foo, Decl(objectSubtypeReduction.ts, 0, 0))
+>x : Symbol(x, Decl(objectSubtypeReduction.ts, 2, 13))
+
+    return Object.entries(x || {})
+>Object.entries(x || {})        .sort : Symbol(sort, Decl(lib.es5.d.ts, --, --))
+>Object.entries : Symbol(entries, Decl(lib.es2017.object.d.ts, --, --), Decl(lib.es2017.object.d.ts, --, --))
+>Object : Symbol(Object, Decl(lib.es5.d.ts, --, --), Decl(lib.es5.d.ts, --, --))
+>entries : Symbol(entries, Decl(lib.es2017.object.d.ts, --, --), Decl(lib.es2017.object.d.ts, --, --))
+>x : Symbol(x, Decl(objectSubtypeReduction.ts, 2, 13))
+
+        .sort(([k1, v1], [k2, v2]) => v1.name.localeCompare(v2.name));
+>sort : Symbol(sort, Decl(lib.es5.d.ts, --, --))
+>k1 : Symbol(k1, Decl(objectSubtypeReduction.ts, 4, 16))
+>v1 : Symbol(v1, Decl(objectSubtypeReduction.ts, 4, 19))
+>k2 : Symbol(k2, Decl(objectSubtypeReduction.ts, 4, 26))
+>v2 : Symbol(v2, Decl(objectSubtypeReduction.ts, 4, 29))
+>v1 : Symbol(v1, Decl(objectSubtypeReduction.ts, 4, 19))
+>v2 : Symbol(v2, Decl(objectSubtypeReduction.ts, 4, 29))
+}
+
diff --git a/testdata/baselines/reference/compiler/objectSubtypeReduction.types b/testdata/baselines/reference/compiler/objectSubtypeReduction.types
new file mode 100644
index 0000000000..cc84cf2e2c
--- /dev/null
+++ b/testdata/baselines/reference/compiler/objectSubtypeReduction.types
@@ -0,0 +1,38 @@
+//// [tests/cases/compiler/objectSubtypeReduction.ts] ////
+
+=== objectSubtypeReduction.ts ===
+// https://github.com/microsoft/typescript-go/issues/1164
+
+function foo(x?: object) {
+>foo : (x?: object | undefined) => [string, any][]
+>x : object | undefined
+
+    return Object.entries(x || {})
+>Object.entries(x || {})        .sort(([k1, v1], [k2, v2]) => v1.name.localeCompare(v2.name)) : [string, any][]
+>Object.entries(x || {})        .sort : (compareFn?: ((a: [string, any], b: [string, any]) => number) | undefined) => [string, any][]
+>Object.entries(x || {}) : [string, any][]
+>Object.entries : { <T>(o: ArrayLike<T> | { [s: string]: T; }): [string, T][]; (o: {}): [string, any][]; }
+>Object : ObjectConstructor
+>entries : { <T>(o: ArrayLike<T> | { [s: string]: T; }): [string, T][]; (o: {}): [string, any][]; }
+>x || {} : object
+>x : object | undefined
+>{} : {}
+
+        .sort(([k1, v1], [k2, v2]) => v1.name.localeCompare(v2.name));
+>sort : (compareFn?: ((a: [string, any], b: [string, any]) => number) | undefined) => [string, any][]
+>([k1, v1], [k2, v2]) => v1.name.localeCompare(v2.name) : ([k1, v1]: [string, any], [k2, v2]: [string, any]) => any
+>k1 : string
+>v1 : any
+>k2 : string
+>v2 : any
+>v1.name.localeCompare(v2.name) : any
+>v1.name.localeCompare : any
+>v1.name : any
+>v1 : any
+>name : any
+>localeCompare : any
+>v2.name : any
+>v2 : any
+>name : any
+}
+
diff --git a/testdata/baselines/reference/submodule/compiler/circularContextualReturnType.types b/testdata/baselines/reference/submodule/compiler/circularContextualReturnType.types
index c70c99f134..f922db2738 100644
--- a/testdata/baselines/reference/submodule/compiler/circularContextualReturnType.types
+++ b/testdata/baselines/reference/submodule/compiler/circularContextualReturnType.types
@@ -5,9 +5,9 @@
 
 Object.freeze({
 >Object.freeze({    foo() {        return Object.freeze('a');    },}) : Readonly<{ foo(): string; }>
->Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object | null | undefined; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
+>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U | null | undefined; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
 >Object : ObjectConstructor
->freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object | null | undefined; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
+>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U | null | undefined; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
 >{    foo() {        return Object.freeze('a');    },} : { foo(): string; }
 
     foo() {
@@ -15,9 +15,9 @@ Object.freeze({
 
         return Object.freeze('a');
 >Object.freeze('a') : string
->Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object | null | undefined; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
+>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U | null | undefined; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
 >Object : ObjectConstructor
->freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object | null | undefined; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
+>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U | null | undefined; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
 >'a' : "a"
 
     },
diff --git a/testdata/baselines/reference/submodule/compiler/circularContextualReturnType.types.diff b/testdata/baselines/reference/submodule/compiler/circularContextualReturnType.types.diff
index 8de456ecc6..d4cae7c8f5 100644
--- a/testdata/baselines/reference/submodule/compiler/circularContextualReturnType.types.diff
+++ b/testdata/baselines/reference/submodule/compiler/circularContextualReturnType.types.diff
@@ -5,10 +5,10 @@
  Object.freeze({
  >Object.freeze({    foo() {        return Object.freeze('a');    },}) : Readonly<{ foo(): string; }>
 ->Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | null | undefined | object; }, U extends string | bigint | number | boolean | symbol>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
-+>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object | null | undefined; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
++>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U | null | undefined; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
  >Object : ObjectConstructor
 ->freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | null | undefined | object; }, U extends string | bigint | number | boolean | symbol>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
-+>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object | null | undefined; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
++>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U | null | undefined; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
  >{    foo() {        return Object.freeze('a');    },} : { foo(): string; }
 
      foo() {
@@ -17,10 +17,10 @@
          return Object.freeze('a');
  >Object.freeze('a') : string
 ->Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | null | undefined | object; }, U extends string | bigint | number | boolean | symbol>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
-+>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object | null | undefined; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
++>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U | null | undefined; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
  >Object : ObjectConstructor
 ->freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | null | undefined | object; }, U extends string | bigint | number | boolean | symbol>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
-+>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object | null | undefined; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
++>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U | null | undefined; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
  >'a' : "a"
 
      },
\ No newline at end of file
diff --git a/testdata/baselines/reference/submodule/compiler/contextualSignatureInObjectFreeze.types b/testdata/baselines/reference/submodule/compiler/contextualSignatureInObjectFreeze.types
index 65ad4971c1..85af5f3c3d 100644
--- a/testdata/baselines/reference/submodule/compiler/contextualSignatureInObjectFreeze.types
+++ b/testdata/baselines/reference/submodule/compiler/contextualSignatureInObjectFreeze.types
@@ -5,9 +5,9 @@
 
 Object.freeze({
 >Object.freeze({    f: function () { }}) : Readonly<{ f: () => void; }>
->Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
+>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
 >Object : ObjectConstructor
->freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
+>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
 >{    f: function () { }} : { f: () => void; }
 
     f: function () { }
diff --git a/testdata/baselines/reference/submodule/compiler/contextualSignatureInObjectFreeze.types.diff b/testdata/baselines/reference/submodule/compiler/contextualSignatureInObjectFreeze.types.diff
index a049c44b4d..40101981ad 100644
--- a/testdata/baselines/reference/submodule/compiler/contextualSignatureInObjectFreeze.types.diff
+++ b/testdata/baselines/reference/submodule/compiler/contextualSignatureInObjectFreeze.types.diff
@@ -5,10 +5,10 @@
  Object.freeze({
  >Object.freeze({    f: function () { }}) : Readonly<{ f: () => void; }>
 ->Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | null | undefined | object; }, U extends string | bigint | number | boolean | symbol>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
-+>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
++>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
  >Object : ObjectConstructor
 ->freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | null | undefined | object; }, U extends string | bigint | number | boolean | symbol>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
-+>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
++>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
  >{    f: function () { }} : { f: () => void; }
 
      f: function () { }
\ No newline at end of file
diff --git a/testdata/baselines/reference/submodule/compiler/correlatedUnions.types b/testdata/baselines/reference/submodule/compiler/correlatedUnions.types
index 41a398fd7f..ba53ae38d7 100644
--- a/testdata/baselines/reference/submodule/compiler/correlatedUnions.types
+++ b/testdata/baselines/reference/submodule/compiler/correlatedUnions.types
@@ -860,15 +860,15 @@ function getConfigOrDefault<T extends keyof Config>(
 >key : T
 
   const assertedCheck = userValue ? userValue! : defaultValue;
->assertedCheck : NonNullable<Partial<Config>[T]>
->userValue ? userValue! : defaultValue : NonNullable<Partial<Config>[T]>
+>assertedCheck : Config[T]
+>userValue ? userValue! : defaultValue : Config[T]
 >userValue : Partial<Config>[T]
 >userValue! : NonNullable<Partial<Config>[T]>
 >userValue : NonNullable<Partial<Config>[T]>
 >defaultValue : Config[T]
 
   return assertedCheck;
->assertedCheck : NonNullable<Partial<Config>[T]>
+>assertedCheck : Config[T]
 }
 
 // repro from #47523
diff --git a/testdata/baselines/reference/submodule/compiler/correlatedUnions.types.diff b/testdata/baselines/reference/submodule/compiler/correlatedUnions.types.diff
index 1e94053bb7..23d299c30c 100644
--- a/testdata/baselines/reference/submodule/compiler/correlatedUnions.types.diff
+++ b/testdata/baselines/reference/submodule/compiler/correlatedUnions.types.diff
@@ -141,4 +141,23 @@
 +><  K extends KeyOfOriginal,  N extends NestedKeyOfOriginalFor<K>>(  original: Original,  mappedFromOriginal: MappedFromOriginal,  key: K,  nestedKey: N): [Original[K][N], MappedFromOriginal[K][N]] => {  return [original[key][nestedKey], mappedFromOriginal[key][nestedKey]];} : <K extends keyof Original, N extends keyof Original[K]>(original: Original, mappedFromOriginal: SameKeys<Original>, key: K, nestedKey: N) => [Original[K][N], SameKeys<Original>[K][N]]
 
    K extends KeyOfOriginal,
-   N extends NestedKeyOfOriginalFor<K>
\ No newline at end of file
+   N extends NestedKeyOfOriginalFor<K>
+@@= skipped -63, +63 lines =@@
+ >key : T
+
+   const assertedCheck = userValue ? userValue! : defaultValue;
+->assertedCheck : NonNullable<Partial<Config>[T]>
+->userValue ? userValue! : defaultValue : NonNullable<Partial<Config>[T]>
++>assertedCheck : Config[T]
++>userValue ? userValue! : defaultValue : Config[T]
+ >userValue : Partial<Config>[T]
+ >userValue! : NonNullable<Partial<Config>[T]>
+ >userValue : NonNullable<Partial<Config>[T]>
+ >defaultValue : Config[T]
+
+   return assertedCheck;
+->assertedCheck : NonNullable<Partial<Config>[T]>
++>assertedCheck : Config[T]
+ }
+
+ // repro from #47523
\ No newline at end of file
diff --git a/testdata/baselines/reference/submodule/compiler/jsEnumTagOnObjectFrozen.types b/testdata/baselines/reference/submodule/compiler/jsEnumTagOnObjectFrozen.types
index 935ccf7ad4..5d912b169c 100644
--- a/testdata/baselines/reference/submodule/compiler/jsEnumTagOnObjectFrozen.types
+++ b/testdata/baselines/reference/submodule/compiler/jsEnumTagOnObjectFrozen.types
@@ -51,9 +51,9 @@ cbThing(type => {
 const Thing = Object.freeze({
 >Thing : Readonly<{ a: "thing"; b: "chill"; }>
 >Object.freeze({    a: "thing",    b: "chill"}) : Readonly<{ a: "thing"; b: "chill"; }>
->Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
+>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
 >Object : ObjectConstructor
->freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
+>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
 >{    a: "thing",    b: "chill"} : { a: "thing"; b: "chill"; }
 
     a: "thing",
diff --git a/testdata/baselines/reference/submodule/compiler/objectFreeze.types b/testdata/baselines/reference/submodule/compiler/objectFreeze.types
index 959c5d0839..c7f5f48145 100644
--- a/testdata/baselines/reference/submodule/compiler/objectFreeze.types
+++ b/testdata/baselines/reference/submodule/compiler/objectFreeze.types
@@ -4,9 +4,9 @@
 const f = Object.freeze(function foo(a: number, b: string) { return false; });
 >f : (a: number, b: string) => false
 >Object.freeze(function foo(a: number, b: string) { return false; }) : (a: number, b: string) => false
->Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
+>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
 >Object : ObjectConstructor
->freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
+>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
 >function foo(a: number, b: string) { return false; } : (a: number, b: string) => false
 >foo : (a: number, b: string) => false
 >a : number
@@ -28,9 +28,9 @@ class C { constructor(a: number) { } }
 const c = Object.freeze(C);
 >c : typeof C
 >Object.freeze(C) : typeof C
->Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
+>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
 >Object : ObjectConstructor
->freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
+>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
 >C : typeof C
 
 new c(1);
@@ -41,9 +41,9 @@ new c(1);
 const a = Object.freeze([1, 2, 3]);
 >a : readonly number[]
 >Object.freeze([1, 2, 3]) : readonly number[]
->Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
+>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
 >Object : ObjectConstructor
->freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
+>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
 >[1, 2, 3] : number[]
 >1 : 1
 >2 : 2
@@ -64,9 +64,9 @@ a[0] = a[2].toString();
 const o = Object.freeze({ a: 1, b: "string", c: true });
 >o : Readonly<{ a: 1; b: "string"; c: true; }>
 >Object.freeze({ a: 1, b: "string", c: true }) : Readonly<{ a: 1; b: "string"; c: true; }>
->Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
+>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
 >Object : ObjectConstructor
->freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
+>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
 >{ a: 1, b: "string", c: true } : { a: 1; b: "string"; c: true; }
 >a : 1
 >1 : 1
diff --git a/testdata/baselines/reference/submodule/compiler/objectFreeze.types.diff b/testdata/baselines/reference/submodule/compiler/objectFreeze.types.diff
index beb23a3898..ed85e596b2 100644
--- a/testdata/baselines/reference/submodule/compiler/objectFreeze.types.diff
+++ b/testdata/baselines/reference/submodule/compiler/objectFreeze.types.diff
@@ -5,10 +5,10 @@
  >f : (a: number, b: string) => false
  >Object.freeze(function foo(a: number, b: string) { return false; }) : (a: number, b: string) => false
 ->Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | null | undefined | object; }, U extends string | bigint | number | boolean | symbol>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
-+>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
++>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
  >Object : ObjectConstructor
 ->freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | null | undefined | object; }, U extends string | bigint | number | boolean | symbol>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
-+>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
++>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
  >function foo(a: number, b: string) { return false; } : (a: number, b: string) => false
  >foo : (a: number, b: string) => false
  >a : number
@@ -17,10 +17,10 @@
  >c : typeof C
  >Object.freeze(C) : typeof C
 ->Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | null | undefined | object; }, U extends string | bigint | number | boolean | symbol>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
-+>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
++>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
  >Object : ObjectConstructor
 ->freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | null | undefined | object; }, U extends string | bigint | number | boolean | symbol>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
-+>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
++>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
  >C : typeof C
 
  new c(1);
@@ -29,10 +29,10 @@
  >a : readonly number[]
  >Object.freeze([1, 2, 3]) : readonly number[]
 ->Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | null | undefined | object; }, U extends string | bigint | number | boolean | symbol>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
-+>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
++>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
  >Object : ObjectConstructor
 ->freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | null | undefined | object; }, U extends string | bigint | number | boolean | symbol>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
-+>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
++>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
  >[1, 2, 3] : number[]
  >1 : 1
  >2 : 2
@@ -41,10 +41,10 @@
  >o : Readonly<{ a: 1; b: "string"; c: true; }>
  >Object.freeze({ a: 1, b: "string", c: true }) : Readonly<{ a: 1; b: "string"; c: true; }>
 ->Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | null | undefined | object; }, U extends string | bigint | number | boolean | symbol>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
-+>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
++>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
  >Object : ObjectConstructor
 ->freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | null | undefined | object; }, U extends string | bigint | number | boolean | symbol>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
-+>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
++>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
  >{ a: 1, b: "string", c: true } : { a: 1; b: "string"; c: true; }
  >a : 1
  >1 : 1
\ No newline at end of file
diff --git a/testdata/baselines/reference/submodule/compiler/objectFreezeLiteralsDontWiden.types b/testdata/baselines/reference/submodule/compiler/objectFreezeLiteralsDontWiden.types
index 514742ad57..bb19eabaf2 100644
--- a/testdata/baselines/reference/submodule/compiler/objectFreezeLiteralsDontWiden.types
+++ b/testdata/baselines/reference/submodule/compiler/objectFreezeLiteralsDontWiden.types
@@ -4,9 +4,9 @@
 const PUPPETEER_REVISIONS = Object.freeze({
 >PUPPETEER_REVISIONS : Readonly<{ chromium: "1011831"; firefox: "latest"; }>
 >Object.freeze({  chromium: '1011831',  firefox: 'latest',}) : Readonly<{ chromium: "1011831"; firefox: "latest"; }>
->Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
+>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
 >Object : ObjectConstructor
->freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
+>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
 >{  chromium: '1011831',  firefox: 'latest',} : { chromium: "1011831"; firefox: "latest"; }
 
   chromium: '1011831',
diff --git a/testdata/baselines/reference/submodule/compiler/objectFreezeLiteralsDontWiden.types.diff b/testdata/baselines/reference/submodule/compiler/objectFreezeLiteralsDontWiden.types.diff
index 2ff83939c6..9abf3495af 100644
--- a/testdata/baselines/reference/submodule/compiler/objectFreezeLiteralsDontWiden.types.diff
+++ b/testdata/baselines/reference/submodule/compiler/objectFreezeLiteralsDontWiden.types.diff
@@ -5,10 +5,10 @@
  >PUPPETEER_REVISIONS : Readonly<{ chromium: "1011831"; firefox: "latest"; }>
  >Object.freeze({  chromium: '1011831',  firefox: 'latest',}) : Readonly<{ chromium: "1011831"; firefox: "latest"; }>
 ->Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | null | undefined | object; }, U extends string | bigint | number | boolean | symbol>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
-+>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
++>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
  >Object : ObjectConstructor
 ->freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | null | undefined | object; }, U extends string | bigint | number | boolean | symbol>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
-+>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
++>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
  >{  chromium: '1011831',  firefox: 'latest',} : { chromium: "1011831"; firefox: "latest"; }
 
    chromium: '1011831',
\ No newline at end of file
diff --git a/testdata/baselines/reference/submodule/compiler/objectFromEntries.types b/testdata/baselines/reference/submodule/compiler/objectFromEntries.types
index 6ba3724e1e..d94b14975a 100644
--- a/testdata/baselines/reference/submodule/compiler/objectFromEntries.types
+++ b/testdata/baselines/reference/submodule/compiler/objectFromEntries.types
@@ -45,9 +45,9 @@ const o3 = Object.fromEntries(new Map([[Symbol("key"), "value"]]));
 const frozenArray = Object.freeze([['a', 1], ['b', 2], ['c', 3]]);
 >frozenArray : readonly (string | number)[][]
 >Object.freeze([['a', 1], ['b', 2], ['c', 3]]) : readonly (string | number)[][]
->Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
+>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
 >Object : ObjectConstructor
->freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
+>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
 >[['a', 1], ['b', 2], ['c', 3]] : (string | number)[][]
 >['a', 1] : (string | number)[]
 >'a' : "a"
@@ -70,9 +70,9 @@ const o4 = Object.fromEntries(frozenArray);
 const frozenArray2: readonly [string, number][] = Object.freeze([['a', 1], ['b', 2], ['c', 3]]);
 >frozenArray2 : readonly [string, number][]
 >Object.freeze([['a', 1], ['b', 2], ['c', 3]]) : readonly [string, number][]
->Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
+>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
 >Object : ObjectConstructor
->freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
+>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
 >[['a', 1], ['b', 2], ['c', 3]] : [string, number][]
 >['a', 1] : [string, number]
 >'a' : "a"
diff --git a/testdata/baselines/reference/submodule/compiler/objectFromEntries.types.diff b/testdata/baselines/reference/submodule/compiler/objectFromEntries.types.diff
index 082c28d2c7..7a8698fd9d 100644
--- a/testdata/baselines/reference/submodule/compiler/objectFromEntries.types.diff
+++ b/testdata/baselines/reference/submodule/compiler/objectFromEntries.types.diff
@@ -14,10 +14,10 @@
  >frozenArray : readonly (string | number)[][]
  >Object.freeze([['a', 1], ['b', 2], ['c', 3]]) : readonly (string | number)[][]
 ->Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | null | undefined | object; }, U extends string | bigint | number | boolean | symbol>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
-+>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
++>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
  >Object : ObjectConstructor
 ->freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | null | undefined | object; }, U extends string | bigint | number | boolean | symbol>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
-+>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
++>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
  >[['a', 1], ['b', 2], ['c', 3]] : (string | number)[][]
  >['a', 1] : (string | number)[]
  >'a' : "a"
@@ -26,10 +26,10 @@
  >frozenArray2 : readonly [string, number][]
  >Object.freeze([['a', 1], ['b', 2], ['c', 3]]) : readonly [string, number][]
 ->Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | null | undefined | object; }, U extends string | bigint | number | boolean | symbol>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
-+>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
++>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
  >Object : ObjectConstructor
 ->freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | null | undefined | object; }, U extends string | bigint | number | boolean | symbol>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
-+>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
++>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
  >[['a', 1], ['b', 2], ['c', 3]] : [string, number][]
  >['a', 1] : [string, number]
  >'a' : "a"
\ No newline at end of file
diff --git a/testdata/baselines/reference/submodule/compiler/objectLiteralExcessProperties.types b/testdata/baselines/reference/submodule/compiler/objectLiteralExcessProperties.types
index 443700cc60..a145c46afd 100644
--- a/testdata/baselines/reference/submodule/compiler/objectLiteralExcessProperties.types
+++ b/testdata/baselines/reference/submodule/compiler/objectLiteralExcessProperties.types
@@ -145,7 +145,7 @@ function test<T extends IFoo>() {
 
     // No excess property checks when union includes 'object' type
     const obj5: object | { x: string } = { z: 'abc' }
->obj5 : { x: string; } | object
+>obj5 : object | { x: string; }
 >x : string
 >{ z: 'abc' } : { z: string; }
 >z : string
diff --git a/testdata/baselines/reference/submodule/compiler/objectLiteralExcessProperties.types.diff b/testdata/baselines/reference/submodule/compiler/objectLiteralExcessProperties.types.diff
index 16cea5d93a..ebfd5a47ca 100644
--- a/testdata/baselines/reference/submodule/compiler/objectLiteralExcessProperties.types.diff
+++ b/testdata/baselines/reference/submodule/compiler/objectLiteralExcessProperties.types.diff
@@ -17,4 +17,13 @@
 +>obj4 : { name: string; } | T & { prop: boolean; }
  >prop : boolean
  >name : string
- >{ name: "test", prop: true } : { name: string; prop: boolean; }
\ No newline at end of file
+ >{ name: "test", prop: true } : { name: string; prop: boolean; }
+@@= skipped -11, +11 lines =@@
+
+     // No excess property checks when union includes 'object' type
+     const obj5: object | { x: string } = { z: 'abc' }
+->obj5 : { x: string; } | object
++>obj5 : object | { x: string; }
+ >x : string
+ >{ z: 'abc' } : { z: string; }
+ >z : string
\ No newline at end of file
diff --git a/testdata/baselines/reference/submodule/compiler/typeGuardConstructorClassAndNumber.types b/testdata/baselines/reference/submodule/compiler/typeGuardConstructorClassAndNumber.types
index 1828cc5e86..5efc141784 100644
--- a/testdata/baselines/reference/submodule/compiler/typeGuardConstructorClassAndNumber.types
+++ b/testdata/baselines/reference/submodule/compiler/typeGuardConstructorClassAndNumber.types
@@ -321,13 +321,13 @@ else {
 // Repro from #37660
 
 function foo(instance: Function | object) {
->foo : (instance: Function | object) => number
->instance : Function | object
+>foo : (instance: object | Function) => number
+>instance : object | Function
 
     if (typeof instance === 'function') {
 >typeof instance === 'function' : boolean
 >typeof instance : "bigint" | "boolean" | "function" | "number" | "object" | "string" | "symbol" | "undefined"
->instance : Function | object
+>instance : object | Function
 >'function' : "function"
 
         if (instance.prototype == null || instance.prototype.constructor == null) {
diff --git a/testdata/baselines/reference/submodule/compiler/typeGuardConstructorClassAndNumber.types.diff b/testdata/baselines/reference/submodule/compiler/typeGuardConstructorClassAndNumber.types.diff
new file mode 100644
index 0000000000..27fb073af6
--- /dev/null
+++ b/testdata/baselines/reference/submodule/compiler/typeGuardConstructorClassAndNumber.types.diff
@@ -0,0 +1,19 @@
+--- old.typeGuardConstructorClassAndNumber.types
++++ new.typeGuardConstructorClassAndNumber.types
+@@= skipped -320, +320 lines =@@
+ // Repro from #37660
+
+ function foo(instance: Function | object) {
+->foo : (instance: Function | object) => number
+->instance : Function | object
++>foo : (instance: object | Function) => number
++>instance : object | Function
+
+     if (typeof instance === 'function') {
+ >typeof instance === 'function' : boolean
+ >typeof instance : "bigint" | "boolean" | "function" | "number" | "object" | "string" | "symbol" | "undefined"
+->instance : Function | object
++>instance : object | Function
+ >'function' : "function"
+
+         if (instance.prototype == null || instance.prototype.constructor == null) {
\ No newline at end of file
diff --git a/testdata/baselines/reference/submodule/compiler/unionOfFunctionAndSignatureIsCallable.types b/testdata/baselines/reference/submodule/compiler/unionOfFunctionAndSignatureIsCallable.types
index 9595619643..62766a08ce 100644
--- a/testdata/baselines/reference/submodule/compiler/unionOfFunctionAndSignatureIsCallable.types
+++ b/testdata/baselines/reference/submodule/compiler/unionOfFunctionAndSignatureIsCallable.types
@@ -26,15 +26,15 @@ function f1(c1: Function, c2: () => object,  callable: typeof c1 | typeof c2) {
 }
 
 function f2(fetcherParams: object | (() => object)) {
->f2 : (fetcherParams: (() => object) | object) => void
->fetcherParams : (() => object) | object
+>f2 : (fetcherParams: object | (() => object)) => void
+>fetcherParams : object | (() => object)
 
     const data = typeof fetcherParams === 'function'
 >data : any
 >typeof fetcherParams === 'function'        ? fetcherParams()        : fetcherParams : any
 >typeof fetcherParams === 'function' : boolean
 >typeof fetcherParams : "bigint" | "boolean" | "function" | "number" | "object" | "string" | "symbol" | "undefined"
->fetcherParams : (() => object) | object
+>fetcherParams : object | (() => object)
 >'function' : "function"
 
         ? fetcherParams()
diff --git a/testdata/baselines/reference/submodule/compiler/unionOfFunctionAndSignatureIsCallable.types.diff b/testdata/baselines/reference/submodule/compiler/unionOfFunctionAndSignatureIsCallable.types.diff
index 9468dc9d69..a88707ecaf 100644
--- a/testdata/baselines/reference/submodule/compiler/unionOfFunctionAndSignatureIsCallable.types.diff
+++ b/testdata/baselines/reference/submodule/compiler/unionOfFunctionAndSignatureIsCallable.types.diff
@@ -21,9 +21,9 @@
  }
 
  function f2(fetcherParams: object | (() => object)) {
-->f2 : (fetcherParams: object | (() => object)) => void
-+>f2 : (fetcherParams: (() => object) | object) => void
- >fetcherParams : (() => object) | object
+ >f2 : (fetcherParams: object | (() => object)) => void
+->fetcherParams : (() => object) | object
++>fetcherParams : object | (() => object)
 
      const data = typeof fetcherParams === 'function'
 ->data : error
@@ -32,7 +32,8 @@
 +>typeof fetcherParams === 'function'        ? fetcherParams()        : fetcherParams : any
  >typeof fetcherParams === 'function' : boolean
  >typeof fetcherParams : "bigint" | "boolean" | "function" | "number" | "object" | "string" | "symbol" | "undefined"
- >fetcherParams : (() => object) | object
+->fetcherParams : (() => object) | object
++>fetcherParams : object | (() => object)
  >'function' : "function"
 
          ? fetcherParams()
diff --git a/testdata/baselines/reference/submodule/compiler/vueLikeDataAndPropsInference2.types b/testdata/baselines/reference/submodule/compiler/vueLikeDataAndPropsInference2.types
index 3ec1e93768..9d7f70804b 100644
--- a/testdata/baselines/reference/submodule/compiler/vueLikeDataAndPropsInference2.types
+++ b/testdata/baselines/reference/submodule/compiler/vueLikeDataAndPropsInference2.types
@@ -45,16 +45,16 @@ type ThisTypedOptions<Data, Props> =
     ThisType<Data & Readonly<Props> & Instance>
 
 declare function test<Data, Props>(fn: ThisTypedOptions<Data, Props>): void;
->test : { <Data, Props>(fn: ThisTypedOptions<Data, Props>): void; (fn: Options<((this: Instance) => object) | object, PropsDefinition<Record<string, any>>>): void; }
+>test : { <Data, Props>(fn: ThisTypedOptions<Data, Props>): void; (fn: Options<object | ((this: Instance) => object), PropsDefinition<Record<string, any>>>): void; }
 >fn : ThisTypedOptions<Data, Props>
 
 declare function test(fn: Options): void;
->test : { <Data, Props>(fn: ThisTypedOptions<Data, Props>): void; (fn: Options<((this: Instance) => object) | object, PropsDefinition<Record<string, any>>>): void; }
->fn : Options<((this: Instance) => object) | object, PropsDefinition<Record<string, any>>>
+>test : { <Data, Props>(fn: ThisTypedOptions<Data, Props>): void; (fn: Options<object | ((this: Instance) => object), PropsDefinition<Record<string, any>>>): void; }
+>fn : Options<object | ((this: Instance) => object), PropsDefinition<Record<string, any>>>
 
 test({
 >test({    props: {        foo: ''    },    data(): { bar: boolean } {        return {            bar: true        }    },    watch: {        foo(newVal: string, oldVal: string): void {            this.bar = false        }    }}) : void
->test : { <Data, Props>(fn: ThisTypedOptions<Data, Props>): void; (fn: Options<((this: Instance) => object) | object, PropsDefinition<Record<string, any>>>): void; }
+>test : { <Data, Props>(fn: ThisTypedOptions<Data, Props>): void; (fn: Options<object | ((this: Instance) => object), PropsDefinition<Record<string, any>>>): void; }
 >{    props: {        foo: ''    },    data(): { bar: boolean } {        return {            bar: true        }    },    watch: {        foo(newVal: string, oldVal: string): void {            this.bar = false        }    }} : { props: { foo: string; }; data(this: Readonly<{ foo: string; }> & Instance): { bar: boolean; }; watch: { foo(newVal: string, oldVal: string): void; }; }
 
     props: {
diff --git a/testdata/baselines/reference/submodule/compiler/vueLikeDataAndPropsInference2.types.diff b/testdata/baselines/reference/submodule/compiler/vueLikeDataAndPropsInference2.types.diff
index b7fbfe77c3..beb4d294c7 100644
--- a/testdata/baselines/reference/submodule/compiler/vueLikeDataAndPropsInference2.types.diff
+++ b/testdata/baselines/reference/submodule/compiler/vueLikeDataAndPropsInference2.types.diff
@@ -5,18 +5,19 @@
 
  declare function test<Data, Props>(fn: ThisTypedOptions<Data, Props>): void;
 ->test : { <Data, Props>(fn: ThisTypedOptions<Data, Props>): void; (fn: Options): void; }
-+>test : { <Data, Props>(fn: ThisTypedOptions<Data, Props>): void; (fn: Options<((this: Instance) => object) | object, PropsDefinition<Record<string, any>>>): void; }
++>test : { <Data, Props>(fn: ThisTypedOptions<Data, Props>): void; (fn: Options<object | ((this: Instance) => object), PropsDefinition<Record<string, any>>>): void; }
  >fn : ThisTypedOptions<Data, Props>
 
  declare function test(fn: Options): void;
 ->test : { <Data, Props>(fn: ThisTypedOptions<Data, Props>): void; (fn: Options): void; }
-+>test : { <Data, Props>(fn: ThisTypedOptions<Data, Props>): void; (fn: Options<((this: Instance) => object) | object, PropsDefinition<Record<string, any>>>): void; }
- >fn : Options<((this: Instance) => object) | object, PropsDefinition<Record<string, any>>>
+->fn : Options<((this: Instance) => object) | object, PropsDefinition<Record<string, any>>>
++>test : { <Data, Props>(fn: ThisTypedOptions<Data, Props>): void; (fn: Options<object | ((this: Instance) => object), PropsDefinition<Record<string, any>>>): void; }
++>fn : Options<object | ((this: Instance) => object), PropsDefinition<Record<string, any>>>
 
  test({
  >test({    props: {        foo: ''    },    data(): { bar: boolean } {        return {            bar: true        }    },    watch: {        foo(newVal: string, oldVal: string): void {            this.bar = false        }    }}) : void
 ->test : { <Data, Props>(fn: ThisTypedOptions<Data, Props>): void; (fn: Options): void; }
-+>test : { <Data, Props>(fn: ThisTypedOptions<Data, Props>): void; (fn: Options<((this: Instance) => object) | object, PropsDefinition<Record<string, any>>>): void; }
++>test : { <Data, Props>(fn: ThisTypedOptions<Data, Props>): void; (fn: Options<object | ((this: Instance) => object), PropsDefinition<Record<string, any>>>): void; }
  >{    props: {        foo: ''    },    data(): { bar: boolean } {        return {            bar: true        }    },    watch: {        foo(newVal: string, oldVal: string): void {            this.bar = false        }    }} : { props: { foo: string; }; data(this: Readonly<{ foo: string; }> & Instance): { bar: boolean; }; watch: { foo(newVal: string, oldVal: string): void; }; }
 
      props: {
\ No newline at end of file
diff --git a/testdata/baselines/reference/submodule/conformance/conditionalTypes2.types b/testdata/baselines/reference/submodule/conformance/conditionalTypes2.types
index 4d09072900..976b54e78b 100644
--- a/testdata/baselines/reference/submodule/conformance/conditionalTypes2.types
+++ b/testdata/baselines/reference/submodule/conformance/conditionalTypes2.types
@@ -277,8 +277,8 @@ interface B1<T> extends A1<T> {
 // Repro from #22899
 
 declare function toString1(value: object | Function): string ;
->toString1 : (value: Function | object) => string
->value : Function | object
+>toString1 : (value: object | Function) => string
+>value : object | Function
 
 declare function toString2(value: Function): string ;
 >toString2 : (value: Function) => string
@@ -295,7 +295,7 @@ function foo<T>(value: T) {
 
         toString1(value);
 >toString1(value) : string
->toString1 : (value: Function | object) => string
+>toString1 : (value: object | Function) => string
 >value : Extract<T, Function>
 
         toString2(value);
diff --git a/testdata/baselines/reference/submodule/conformance/conditionalTypes2.types.diff b/testdata/baselines/reference/submodule/conformance/conditionalTypes2.types.diff
index 6b5ba46c47..276c5aa2c2 100644
--- a/testdata/baselines/reference/submodule/conformance/conditionalTypes2.types.diff
+++ b/testdata/baselines/reference/submodule/conformance/conditionalTypes2.types.diff
@@ -9,25 +9,16 @@
  >predicate : (v: T) => boolean
  >v : T
 
-@@= skipped -28, +28 lines =@@
- // Repro from #22899
+@@= skipped -29, +29 lines =@@
 
  declare function toString1(value: object | Function): string ;
-->toString1 : (value: object | Function) => string
-+>toString1 : (value: Function | object) => string
- >value : Function | object
+ >toString1 : (value: object | Function) => string
+->value : Function | object
++>value : object | Function
 
  declare function toString2(value: Function): string ;
-@@= skipped -18, +18 lines =@@
-
-         toString1(value);
- >toString1(value) : string
-->toString1 : (value: object | Function) => string
-+>toString1 : (value: Function | object) => string
- >value : Extract<T, Function>
-
-         toString2(value);
-@@= skipped -156, +156 lines =@@
+ >toString2 : (value: Function) => string
+@@= skipped -173, +173 lines =@@
  // Repro from #33568
 
  declare function save(_response: IRootResponse<string>): void;
diff --git a/testdata/baselines/reference/submodule/conformance/generatorYieldContextualType.types b/testdata/baselines/reference/submodule/conformance/generatorYieldContextualType.types
index cb7d7fb1c5..fb0d700541 100644
--- a/testdata/baselines/reference/submodule/conformance/generatorYieldContextualType.types
+++ b/testdata/baselines/reference/submodule/conformance/generatorYieldContextualType.types
@@ -192,7 +192,7 @@ type StepState<T = Record<string, unknown>> = T & {
 };
 
 function canPickStepContinue<T extends QuickPickStep>(
->canPickStepContinue : <T extends QuickPickStep<QuickPickItem>>(_step: T, _state: PartialStepState<unknown>, _selection: Directive | StepItemType<T>) => _selection is StepItemType<T>
+>canPickStepContinue : <T extends QuickPickStep<QuickPickItem>>(_step: T, _state: PartialStepState<unknown>, _selection: StepItemType<T> | Directive) => _selection is StepItemType<T>
 
   _step: T,
 >_step : T
@@ -201,7 +201,7 @@ function canPickStepContinue<T extends QuickPickStep>(
 >_state : PartialStepState<unknown>
 
   _selection: StepItemType<T> | Directive
->_selection : Directive | StepItemType<T>
+>_selection : StepItemType<T> | Directive
 
 ): _selection is StepItemType<T> {
   return false;
@@ -258,7 +258,7 @@ function* showStep<
   return canPickStepContinue(step, state, selection)
 >canPickStepContinue(step, state, selection)    ? selection[0]    : StepResult.Break : unique symbol | QuickPickItem
 >canPickStepContinue(step, state, selection) : boolean
->canPickStepContinue : <T extends QuickPickStep<QuickPickItem>>(_step: T, _state: PartialStepState<unknown>, _selection: Directive | StepItemType<T>) => _selection is StepItemType<T>
+>canPickStepContinue : <T extends QuickPickStep<QuickPickItem>>(_step: T, _state: PartialStepState<unknown>, _selection: StepItemType<T> | Directive) => _selection is StepItemType<T>
 >step : QuickPickStep<QuickPickItem>
 >state : State
 >selection : QuickPickItem[] | Directive
diff --git a/testdata/baselines/reference/submodule/conformance/generatorYieldContextualType.types.diff b/testdata/baselines/reference/submodule/conformance/generatorYieldContextualType.types.diff
index 024ea2474a..231e317d4c 100644
--- a/testdata/baselines/reference/submodule/conformance/generatorYieldContextualType.types.diff
+++ b/testdata/baselines/reference/submodule/conformance/generatorYieldContextualType.types.diff
@@ -42,11 +42,20 @@
 
  function canPickStepContinue<T extends QuickPickStep>(
 ->canPickStepContinue : <T extends QuickPickStep>(_step: T, _state: PartialStepState, _selection: StepItemType<T> | Directive) => _selection is StepItemType<T>
-+>canPickStepContinue : <T extends QuickPickStep<QuickPickItem>>(_step: T, _state: PartialStepState<unknown>, _selection: Directive | StepItemType<T>) => _selection is StepItemType<T>
++>canPickStepContinue : <T extends QuickPickStep<QuickPickItem>>(_step: T, _state: PartialStepState<unknown>, _selection: StepItemType<T> | Directive) => _selection is StepItemType<T>
 
    _step: T,
  >_step : T
-@@= skipped -28, +28 lines =@@
+@@= skipped -9, +9 lines =@@
+ >_state : PartialStepState<unknown>
+
+   _selection: StepItemType<T> | Directive
+->_selection : Directive | StepItemType<T>
++>_selection : StepItemType<T> | Directive
+
+ ): _selection is StepItemType<T> {
+   return false;
+@@= skipped -19, +19 lines =@@
  }
 
  function* showStep<
@@ -60,7 +69,7 @@
  >canPickStepContinue(step, state, selection)    ? selection[0]    : StepResult.Break : unique symbol | QuickPickItem
  >canPickStepContinue(step, state, selection) : boolean
 ->canPickStepContinue : <T extends QuickPickStep>(_step: T, _state: PartialStepState, _selection: StepItemType<T> | Directive) => _selection is StepItemType<T>
-+>canPickStepContinue : <T extends QuickPickStep<QuickPickItem>>(_step: T, _state: PartialStepState<unknown>, _selection: Directive | StepItemType<T>) => _selection is StepItemType<T>
++>canPickStepContinue : <T extends QuickPickStep<QuickPickItem>>(_step: T, _state: PartialStepState<unknown>, _selection: StepItemType<T> | Directive) => _selection is StepItemType<T>
  >step : QuickPickStep<QuickPickItem>
  >state : State
  >selection : QuickPickItem[] | Directive
\ No newline at end of file
diff --git a/testdata/baselines/reference/submodule/conformance/inOperatorWithValidOperands.errors.txt b/testdata/baselines/reference/submodule/conformance/inOperatorWithValidOperands.errors.txt
index 626bfc1a7e..0fad942f62 100644
--- a/testdata/baselines/reference/submodule/conformance/inOperatorWithValidOperands.errors.txt
+++ b/testdata/baselines/reference/submodule/conformance/inOperatorWithValidOperands.errors.txt
@@ -1,7 +1,7 @@
 inOperatorWithValidOperands.ts(26,20): error TS2322: Type 'T' is not assignable to type 'object'.
 inOperatorWithValidOperands.ts(30,20): error TS2322: Type 'T | U' is not assignable to type 'object'.
   Type 'T' is not assignable to type 'object'.
-inOperatorWithValidOperands.ts(34,20): error TS2322: Type 'T | object' is not assignable to type 'object'.
+inOperatorWithValidOperands.ts(34,20): error TS2322: Type 'object | T' is not assignable to type 'object'.
   Type 'T' is not assignable to type 'object'.
 
 
@@ -48,7 +48,7 @@ inOperatorWithValidOperands.ts(34,20): error TS2322: Type 'T | object' is not as
     function unionCase2<T>(t: T | object) {
         var rb5 = x in t;
                        ~
-!!! error TS2322: Type 'T | object' is not assignable to type 'object'.
+!!! error TS2322: Type 'object | T' is not assignable to type 'object'.
 !!! error TS2322:   Type 'T' is not assignable to type 'object'.
 !!! related TS2208 inOperatorWithValidOperands.ts:33:21: This type parameter might need an `extends object` constraint.
     }
diff --git a/testdata/baselines/reference/submodule/conformance/inOperatorWithValidOperands.errors.txt.diff b/testdata/baselines/reference/submodule/conformance/inOperatorWithValidOperands.errors.txt.diff
new file mode 100644
index 0000000000..db953e8336
--- /dev/null
+++ b/testdata/baselines/reference/submodule/conformance/inOperatorWithValidOperands.errors.txt.diff
@@ -0,0 +1,20 @@
+--- old.inOperatorWithValidOperands.errors.txt
++++ new.inOperatorWithValidOperands.errors.txt
+@@= skipped -0, +0 lines =@@
+ inOperatorWithValidOperands.ts(26,20): error TS2322: Type 'T' is not assignable to type 'object'.
+ inOperatorWithValidOperands.ts(30,20): error TS2322: Type 'T | U' is not assignable to type 'object'.
+   Type 'T' is not assignable to type 'object'.
+-inOperatorWithValidOperands.ts(34,20): error TS2322: Type 'T | object' is not assignable to type 'object'.
++inOperatorWithValidOperands.ts(34,20): error TS2322: Type 'object | T' is not assignable to type 'object'.
+   Type 'T' is not assignable to type 'object'.
+
+
+@@= skipped -47, +47 lines =@@
+     function unionCase2<T>(t: T | object) {
+         var rb5 = x in t;
+                        ~
+-!!! error TS2322: Type 'T | object' is not assignable to type 'object'.
++!!! error TS2322: Type 'object | T' is not assignable to type 'object'.
+ !!! error TS2322:   Type 'T' is not assignable to type 'object'.
+ !!! related TS2208 inOperatorWithValidOperands.ts:33:21: This type parameter might need an `extends object` constraint.
+     }
\ No newline at end of file
diff --git a/testdata/baselines/reference/submodule/conformance/inOperatorWithValidOperands.types b/testdata/baselines/reference/submodule/conformance/inOperatorWithValidOperands.types
index 22673ba3df..ac09a7708f 100644
--- a/testdata/baselines/reference/submodule/conformance/inOperatorWithValidOperands.types
+++ b/testdata/baselines/reference/submodule/conformance/inOperatorWithValidOperands.types
@@ -100,14 +100,14 @@ function unionCase<T, U>(t: T | U) {
 }
 
 function unionCase2<T>(t: T | object) {
->unionCase2 : <T>(t: T | object) => void
->t : T | object
+>unionCase2 : <T>(t: object | T) => void
+>t : object | T
 
     var rb5 = x in t;
 >rb5 : boolean
 >x in t : boolean
 >x : any
->t : T | object
+>t : object | T
 }
 
 interface X { x: number }
diff --git a/testdata/baselines/reference/submodule/conformance/inOperatorWithValidOperands.types.diff b/testdata/baselines/reference/submodule/conformance/inOperatorWithValidOperands.types.diff
new file mode 100644
index 0000000000..5fc7f20707
--- /dev/null
+++ b/testdata/baselines/reference/submodule/conformance/inOperatorWithValidOperands.types.diff
@@ -0,0 +1,20 @@
+--- old.inOperatorWithValidOperands.types
++++ new.inOperatorWithValidOperands.types
+@@= skipped -99, +99 lines =@@
+ }
+
+ function unionCase2<T>(t: T | object) {
+->unionCase2 : <T>(t: T | object) => void
+->t : T | object
++>unionCase2 : <T>(t: object | T) => void
++>t : object | T
+
+     var rb5 = x in t;
+ >rb5 : boolean
+ >x in t : boolean
+ >x : any
+->t : T | object
++>t : object | T
+ }
+
+ interface X { x: number }
\ No newline at end of file
diff --git a/testdata/baselines/reference/submodule/conformance/keyofAndIndexedAccess.types b/testdata/baselines/reference/submodule/conformance/keyofAndIndexedAccess.types
index 289ba942d3..41c7726b3f 100644
--- a/testdata/baselines/reference/submodule/conformance/keyofAndIndexedAccess.types
+++ b/testdata/baselines/reference/submodule/conformance/keyofAndIndexedAccess.types
@@ -1876,9 +1876,9 @@ class SampleClass<P> {
 >this : this
 >props : Readonly<P>
 >Object.freeze(props) : Readonly<P>
->Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object | null | undefined; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
+>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U | null | undefined; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
 >Object : ObjectConstructor
->freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object | null | undefined; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
+>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U | null | undefined; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
 >props : P
     }
 }
diff --git a/testdata/baselines/reference/submodule/conformance/keyofAndIndexedAccess.types.diff b/testdata/baselines/reference/submodule/conformance/keyofAndIndexedAccess.types.diff
index 3ab9357a1c..4fd830c61b 100644
--- a/testdata/baselines/reference/submodule/conformance/keyofAndIndexedAccess.types.diff
+++ b/testdata/baselines/reference/submodule/conformance/keyofAndIndexedAccess.types.diff
@@ -184,10 +184,10 @@
  >props : Readonly<P>
  >Object.freeze(props) : Readonly<P>
 ->Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | null | undefined | object; }, U extends string | bigint | number | boolean | symbol>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
-+>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object | null | undefined; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
++>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U | null | undefined; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
  >Object : ObjectConstructor
 ->freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | null | undefined | object; }, U extends string | bigint | number | boolean | symbol>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
-+>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object | null | undefined; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
++>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U | null | undefined; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
  >props : P
      }
  }
diff --git a/testdata/baselines/reference/submodule/conformance/nonPrimitiveAndTypeVariables.errors.txt b/testdata/baselines/reference/submodule/conformance/nonPrimitiveAndTypeVariables.errors.txt
index c5d319776b..2929c9cd00 100644
--- a/testdata/baselines/reference/submodule/conformance/nonPrimitiveAndTypeVariables.errors.txt
+++ b/testdata/baselines/reference/submodule/conformance/nonPrimitiveAndTypeVariables.errors.txt
@@ -1,5 +1,5 @@
 nonPrimitiveAndTypeVariables.ts(10,9): error TS2322: Type 'T' is not assignable to type 'object'.
-nonPrimitiveAndTypeVariables.ts(11,9): error TS2322: Type 'T' is not assignable to type 'U | object'.
+nonPrimitiveAndTypeVariables.ts(11,9): error TS2322: Type 'T' is not assignable to type 'object | U'.
 
 
 ==== nonPrimitiveAndTypeVariables.ts (2 errors) ====
@@ -18,7 +18,7 @@ nonPrimitiveAndTypeVariables.ts(11,9): error TS2322: Type 'T' is not assignable
 !!! related TS2208 nonPrimitiveAndTypeVariables.ts:9:14: This type parameter might need an `extends object` constraint.
         let b: U | object = x;  // Error
             ~
-!!! error TS2322: Type 'T' is not assignable to type 'U | object'.
-!!! related TS2208 nonPrimitiveAndTypeVariables.ts:9:14: This type parameter might need an `extends U | object` constraint.
+!!! error TS2322: Type 'T' is not assignable to type 'object | U'.
+!!! related TS2208 nonPrimitiveAndTypeVariables.ts:9:14: This type parameter might need an `extends object | U` constraint.
     }
     
\ No newline at end of file
diff --git a/testdata/baselines/reference/submodule/conformance/nonPrimitiveAndTypeVariables.errors.txt.diff b/testdata/baselines/reference/submodule/conformance/nonPrimitiveAndTypeVariables.errors.txt.diff
new file mode 100644
index 0000000000..c31a26f2e1
--- /dev/null
+++ b/testdata/baselines/reference/submodule/conformance/nonPrimitiveAndTypeVariables.errors.txt.diff
@@ -0,0 +1,19 @@
+--- old.nonPrimitiveAndTypeVariables.errors.txt
++++ new.nonPrimitiveAndTypeVariables.errors.txt
+@@= skipped -0, +0 lines =@@
+ nonPrimitiveAndTypeVariables.ts(10,9): error TS2322: Type 'T' is not assignable to type 'object'.
+-nonPrimitiveAndTypeVariables.ts(11,9): error TS2322: Type 'T' is not assignable to type 'U | object'.
++nonPrimitiveAndTypeVariables.ts(11,9): error TS2322: Type 'T' is not assignable to type 'object | U'.
+
+
+ ==== nonPrimitiveAndTypeVariables.ts (2 errors) ====
+@@= skipped -17, +17 lines =@@
+ !!! related TS2208 nonPrimitiveAndTypeVariables.ts:9:14: This type parameter might need an `extends object` constraint.
+         let b: U | object = x;  // Error
+             ~
+-!!! error TS2322: Type 'T' is not assignable to type 'U | object'.
+-!!! related TS2208 nonPrimitiveAndTypeVariables.ts:9:14: This type parameter might need an `extends U | object` constraint.
++!!! error TS2322: Type 'T' is not assignable to type 'object | U'.
++!!! related TS2208 nonPrimitiveAndTypeVariables.ts:9:14: This type parameter might need an `extends object | U` constraint.
+     }
+     
\ No newline at end of file
diff --git a/testdata/baselines/reference/submodule/conformance/nonPrimitiveAndTypeVariables.types b/testdata/baselines/reference/submodule/conformance/nonPrimitiveAndTypeVariables.types
index 11b929aa25..49259df111 100644
--- a/testdata/baselines/reference/submodule/conformance/nonPrimitiveAndTypeVariables.types
+++ b/testdata/baselines/reference/submodule/conformance/nonPrimitiveAndTypeVariables.types
@@ -32,7 +32,7 @@ function foo<T, U>(x: T) {
 >x : T
 
     let b: U | object = x;  // Error
->b : U | object
+>b : object | U
 >x : T
 }
 
diff --git a/testdata/baselines/reference/submodule/conformance/nonPrimitiveAndTypeVariables.types.diff b/testdata/baselines/reference/submodule/conformance/nonPrimitiveAndTypeVariables.types.diff
new file mode 100644
index 0000000000..234342215b
--- /dev/null
+++ b/testdata/baselines/reference/submodule/conformance/nonPrimitiveAndTypeVariables.types.diff
@@ -0,0 +1,10 @@
+--- old.nonPrimitiveAndTypeVariables.types
++++ new.nonPrimitiveAndTypeVariables.types
+@@= skipped -31, +31 lines =@@
+ >x : T
+
+     let b: U | object = x;  // Error
+->b : U | object
++>b : object | U
+ >x : T
+ }
diff --git a/testdata/baselines/reference/submodule/conformance/spreadObjectOrFalsy.types b/testdata/baselines/reference/submodule/conformance/spreadObjectOrFalsy.types
index f7a12a178a..270318d4fe 100644
--- a/testdata/baselines/reference/submodule/conformance/spreadObjectOrFalsy.types
+++ b/testdata/baselines/reference/submodule/conformance/spreadObjectOrFalsy.types
@@ -29,12 +29,12 @@ function f3<T extends undefined>(a: T) {
 }
 
 function f4<T extends undefined>(a: object | T) {
->f4 : <T extends undefined>(a: T | object) => {}
->a : T | object
+>f4 : <T extends undefined>(a: object | T) => {}
+>a : object | T
 
     return { ...a };
 >{ ...a } : {}
->a : T | object
+>a : object | T
 }
 
 function f5<S, T extends undefined>(a: S | T) {
diff --git a/testdata/baselines/reference/submodule/conformance/spreadObjectOrFalsy.types.diff b/testdata/baselines/reference/submodule/conformance/spreadObjectOrFalsy.types.diff
index eb41bf49a8..c53237d855 100644
--- a/testdata/baselines/reference/submodule/conformance/spreadObjectOrFalsy.types.diff
+++ b/testdata/baselines/reference/submodule/conformance/spreadObjectOrFalsy.types.diff
@@ -17,16 +17,21 @@
  }
 
  function f3<T extends undefined>(a: T) {
-@@= skipped -18, +18 lines =@@
- }
+@@= skipped -19, +19 lines =@@
 
  function f4<T extends undefined>(a: object | T) {
-->f4 : <T extends undefined>(a: object | T) => {}
-+>f4 : <T extends undefined>(a: T | object) => {}
- >a : T | object
+ >f4 : <T extends undefined>(a: object | T) => {}
+->a : T | object
++>a : object | T
 
      return { ...a };
-@@= skipped -29, +29 lines =@@
+ >{ ...a } : {}
+->a : T | object
++>a : object | T
+ }
+
+ function f5<S, T extends undefined>(a: S | T) {
+@@= skipped -28, +28 lines =@@
  // Repro from #46976
 
  function g1<T extends {}, A extends { z: (T | undefined) & T }>(a: A) {
diff --git a/testdata/baselines/reference/submodule/conformance/templateLiteralTypes3.types b/testdata/baselines/reference/submodule/conformance/templateLiteralTypes3.types
index ccb68885a0..6f2290166e 100644
--- a/testdata/baselines/reference/submodule/conformance/templateLiteralTypes3.types
+++ b/testdata/baselines/reference/submodule/conformance/templateLiteralTypes3.types
@@ -608,16 +608,16 @@ function a<T extends {id: string}>() {
 >id : string
 
     let x: keyof T & string | `-${keyof T & string}`;
->x : keyof T & string | `-${keyof T & string}`
+>x : `-${keyof T & string}` | keyof T & string
 
     x = "id";
 >x = "id" : "id"
->x : keyof T & string | `-${keyof T & string}`
+>x : `-${keyof T & string}` | keyof T & string
 >"id" : "id"
 
     x = "-id";
 >x = "-id" : "-id"
->x : keyof T & string | `-${keyof T & string}`
+>x : `-${keyof T & string}` | keyof T & string
 >"-id" : "-id"
 }
 
diff --git a/testdata/baselines/reference/submodule/conformance/templateLiteralTypes3.types.diff b/testdata/baselines/reference/submodule/conformance/templateLiteralTypes3.types.diff
index 1b3a813aef..a80b9d28ec 100644
--- a/testdata/baselines/reference/submodule/conformance/templateLiteralTypes3.types.diff
+++ b/testdata/baselines/reference/submodule/conformance/templateLiteralTypes3.types.diff
@@ -112,17 +112,17 @@
 
      let x: keyof T & string | `-${keyof T & string}`;
 ->x : (keyof T & string) | `-${keyof T & string}`
-+>x : keyof T & string | `-${keyof T & string}`
++>x : `-${keyof T & string}` | keyof T & string
 
      x = "id";
  >x = "id" : "id"
 ->x : (keyof T & string) | `-${keyof T & string}`
-+>x : keyof T & string | `-${keyof T & string}`
++>x : `-${keyof T & string}` | keyof T & string
  >"id" : "id"
 
      x = "-id";
  >x = "-id" : "-id"
 ->x : (keyof T & string) | `-${keyof T & string}`
-+>x : keyof T & string | `-${keyof T & string}`
++>x : `-${keyof T & string}` | keyof T & string
  >"-id" : "-id"
  }
diff --git a/testdata/baselines/reference/submoduleAccepted/compiler/jsEnumTagOnObjectFrozen.types.diff b/testdata/baselines/reference/submoduleAccepted/compiler/jsEnumTagOnObjectFrozen.types.diff
index 8ba89ee226..9bbf9a36b2 100644
--- a/testdata/baselines/reference/submoduleAccepted/compiler/jsEnumTagOnObjectFrozen.types.diff
+++ b/testdata/baselines/reference/submoduleAccepted/compiler/jsEnumTagOnObjectFrozen.types.diff
@@ -40,10 +40,10 @@
  >Thing : Readonly<{ a: "thing"; b: "chill"; }>
  >Object.freeze({    a: "thing",    b: "chill"}) : Readonly<{ a: "thing"; b: "chill"; }>
 ->Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | null | undefined | object; }, U extends string | bigint | number | boolean | symbol>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
-+>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
++>Object.freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
  >Object : ObjectConstructor
 ->freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | null | undefined | object; }, U extends string | bigint | number | boolean | symbol>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
-+>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: U | object; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
++>freeze : { <T extends Function>(f: T): T; <T extends { [idx: string]: object | U; }, U extends string | number | bigint | symbol | boolean>(o: T): Readonly<T>; <T>(o: T): Readonly<T>; }
  >{    a: "thing",    b: "chill"} : { a: "thing"; b: "chill"; }
 
      a: "thing",
diff --git a/testdata/tests/cases/compiler/objectSubtypeReduction.ts b/testdata/tests/cases/compiler/objectSubtypeReduction.ts
new file mode 100644
index 0000000000..65ba68d8c0
--- /dev/null
+++ b/testdata/tests/cases/compiler/objectSubtypeReduction.ts
@@ -0,0 +1,10 @@
+// @strict: true
+// @target: esnext
+// @noEmit: true
+
+// https://github.com/microsoft/typescript-go/issues/1164
+
+function foo(x?: object) {
+    return Object.entries(x || {})
+        .sort(([k1, v1], [k2, v2]) => v1.name.localeCompare(v2.name));
+}