diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 189d82eeab9..90d453bcd99 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -13980,7 +13980,7 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
             for (const current of type.types) {
                 for (const prop of getPropertiesOfType(current)) {
                     if (!members.has(prop.escapedName)) {
-                        const combinedProp = getPropertyOfUnionOrIntersectionType(type, prop.escapedName);
+                        const combinedProp = getPropertyOfUnionOrIntersectionType(type, prop.escapedName, /*skipObjectFunctionPropertyAugment*/ !!(type.flags & TypeFlags.Intersection));
                         if (combinedProp) {
                             members.set(prop.escapedName, combinedProp);
                         }
@@ -14629,6 +14629,10 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
                     type.propertyCacheWithoutObjectFunctionPropertyAugment ||= createSymbolTable() :
                     type.propertyCache ||= createSymbolTable();
                 properties.set(name, property);
+                if (skipObjectFunctionPropertyAugment && !type.propertyCache?.get(name)) {
+                    const properties = type.propertyCache ||= createSymbolTable();
+                    properties.set(name, property);
+                }
             }
         }
         return property;
@@ -14771,7 +14775,17 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
             }
             return getPropertyOfObjectType(globalObjectType, name);
         }
-        if (type.flags & TypeFlags.UnionOrIntersection) {
+        if (type.flags & TypeFlags.Intersection) {
+            const prop = getPropertyOfUnionOrIntersectionType(type as UnionOrIntersectionType, name, /*skipObjectFunctionPropertyAugment*/ true);
+            if (prop) {
+                return prop;
+            }
+            if (!skipObjectFunctionPropertyAugment) {
+                return getPropertyOfUnionOrIntersectionType(type as UnionOrIntersectionType, name, skipObjectFunctionPropertyAugment);
+            }
+            return undefined;
+        }
+        if (type.flags & TypeFlags.Union) {
             return getPropertyOfUnionOrIntersectionType(type as UnionOrIntersectionType, name, skipObjectFunctionPropertyAugment);
         }
         return undefined;
diff --git a/tests/baselines/reference/intersectionIncludingPropFromGlobalAugmentation.symbols b/tests/baselines/reference/intersectionIncludingPropFromGlobalAugmentation.symbols
new file mode 100644
index 00000000000..034306a4d3a
--- /dev/null
+++ b/tests/baselines/reference/intersectionIncludingPropFromGlobalAugmentation.symbols
@@ -0,0 +1,37 @@
+//// [tests/cases/conformance/types/typeRelationships/assignmentCompatibility/intersectionIncludingPropFromGlobalAugmentation.ts] ////
+
+=== intersectionIncludingPropFromGlobalAugmentation.ts ===
+// repro from https://github.com/microsoft/TypeScript/issues/54345
+
+interface Test1 { toString: null | 'string'; }
+>Test1 : Symbol(Test1, Decl(intersectionIncludingPropFromGlobalAugmentation.ts, 0, 0))
+>toString : Symbol(Test1.toString, Decl(intersectionIncludingPropFromGlobalAugmentation.ts, 2, 17))
+
+type Test2 = Test1 & { optional?: unknown };
+>Test2 : Symbol(Test2, Decl(intersectionIncludingPropFromGlobalAugmentation.ts, 2, 46))
+>Test1 : Symbol(Test1, Decl(intersectionIncludingPropFromGlobalAugmentation.ts, 0, 0))
+>optional : Symbol(optional, Decl(intersectionIncludingPropFromGlobalAugmentation.ts, 3, 22))
+
+declare const source: Test1;
+>source : Symbol(source, Decl(intersectionIncludingPropFromGlobalAugmentation.ts, 4, 13))
+>Test1 : Symbol(Test1, Decl(intersectionIncludingPropFromGlobalAugmentation.ts, 0, 0))
+
+const target: Test2 = { ...source };
+>target : Symbol(target, Decl(intersectionIncludingPropFromGlobalAugmentation.ts, 5, 5))
+>Test2 : Symbol(Test2, Decl(intersectionIncludingPropFromGlobalAugmentation.ts, 2, 46))
+>source : Symbol(source, Decl(intersectionIncludingPropFromGlobalAugmentation.ts, 4, 13))
+
+const toString = target.toString;
+>toString : Symbol(toString, Decl(intersectionIncludingPropFromGlobalAugmentation.ts, 7, 5))
+>target.toString : Symbol(Test1.toString, Decl(intersectionIncludingPropFromGlobalAugmentation.ts, 2, 17))
+>target : Symbol(target, Decl(intersectionIncludingPropFromGlobalAugmentation.ts, 5, 5))
+>toString : Symbol(Test1.toString, Decl(intersectionIncludingPropFromGlobalAugmentation.ts, 2, 17))
+
+const hasOwn = target.hasOwnProperty; // not an own member but it should still be accessible
+>hasOwn : Symbol(hasOwn, Decl(intersectionIncludingPropFromGlobalAugmentation.ts, 8, 5))
+>target.hasOwnProperty : Symbol(Object.hasOwnProperty, Decl(lib.es5.d.ts, --, --))
+>target : Symbol(target, Decl(intersectionIncludingPropFromGlobalAugmentation.ts, 5, 5))
+>hasOwnProperty : Symbol(Object.hasOwnProperty, Decl(lib.es5.d.ts, --, --))
+
+export {}
+
diff --git a/tests/baselines/reference/intersectionIncludingPropFromGlobalAugmentation.types b/tests/baselines/reference/intersectionIncludingPropFromGlobalAugmentation.types
new file mode 100644
index 00000000000..8133c1d8985
--- /dev/null
+++ b/tests/baselines/reference/intersectionIncludingPropFromGlobalAugmentation.types
@@ -0,0 +1,34 @@
+//// [tests/cases/conformance/types/typeRelationships/assignmentCompatibility/intersectionIncludingPropFromGlobalAugmentation.ts] ////
+
+=== intersectionIncludingPropFromGlobalAugmentation.ts ===
+// repro from https://github.com/microsoft/TypeScript/issues/54345
+
+interface Test1 { toString: null | 'string'; }
+>toString : "string" | null
+
+type Test2 = Test1 & { optional?: unknown };
+>Test2 : Test1 & { optional?: unknown; }
+>optional : unknown
+
+declare const source: Test1;
+>source : Test1
+
+const target: Test2 = { ...source };
+>target : Test2
+>{ ...source } : { toString: "string" | null; }
+>source : Test1
+
+const toString = target.toString;
+>toString : "string" | null
+>target.toString : "string" | null
+>target : Test2
+>toString : "string" | null
+
+const hasOwn = target.hasOwnProperty; // not an own member but it should still be accessible
+>hasOwn : (v: PropertyKey) => boolean
+>target.hasOwnProperty : (v: PropertyKey) => boolean
+>target : Test2
+>hasOwnProperty : (v: PropertyKey) => boolean
+
+export {}
+
diff --git a/tests/baselines/reference/intersectionWithConstructSignaturePrototypeResult.symbols b/tests/baselines/reference/intersectionWithConstructSignaturePrototypeResult.symbols
new file mode 100644
index 00000000000..a7673bd8bcd
--- /dev/null
+++ b/tests/baselines/reference/intersectionWithConstructSignaturePrototypeResult.symbols
@@ -0,0 +1,39 @@
+//// [tests/cases/compiler/intersectionWithConstructSignaturePrototypeResult.ts] ////
+
+=== intersectionWithConstructSignaturePrototypeResult.ts ===
+declare class EmberObject {}
+>EmberObject : Symbol(EmberObject, Decl(intersectionWithConstructSignaturePrototypeResult.ts, 0, 0))
+
+type PersonType = Readonly<typeof EmberObject> &
+>PersonType : Symbol(PersonType, Decl(intersectionWithConstructSignaturePrototypeResult.ts, 0, 28))
+>Readonly : Symbol(Readonly, Decl(lib.es5.d.ts, --, --))
+>EmberObject : Symbol(EmberObject, Decl(intersectionWithConstructSignaturePrototypeResult.ts, 0, 0))
+
+  (new (properties?: object) => {
+>properties : Symbol(properties, Decl(intersectionWithConstructSignaturePrototypeResult.ts, 3, 8))
+
+    firstName: string;
+>firstName : Symbol(firstName, Decl(intersectionWithConstructSignaturePrototypeResult.ts, 3, 33))
+
+    lastName: string;
+>lastName : Symbol(lastName, Decl(intersectionWithConstructSignaturePrototypeResult.ts, 4, 22))
+
+  } & EmberObject) &
+>EmberObject : Symbol(EmberObject, Decl(intersectionWithConstructSignaturePrototypeResult.ts, 0, 0))
+
+  (new (...args: any[]) => {
+>args : Symbol(args, Decl(intersectionWithConstructSignaturePrototypeResult.ts, 7, 8))
+
+    firstName: string;
+>firstName : Symbol(firstName, Decl(intersectionWithConstructSignaturePrototypeResult.ts, 7, 28))
+
+    lastName: string;
+>lastName : Symbol(lastName, Decl(intersectionWithConstructSignaturePrototypeResult.ts, 8, 22))
+
+  } & EmberObject);
+>EmberObject : Symbol(EmberObject, Decl(intersectionWithConstructSignaturePrototypeResult.ts, 0, 0))
+
+type PersonPrototype = PersonType["prototype"];
+>PersonPrototype : Symbol(PersonPrototype, Decl(intersectionWithConstructSignaturePrototypeResult.ts, 10, 19))
+>PersonType : Symbol(PersonType, Decl(intersectionWithConstructSignaturePrototypeResult.ts, 0, 28))
+
diff --git a/tests/baselines/reference/intersectionWithConstructSignaturePrototypeResult.types b/tests/baselines/reference/intersectionWithConstructSignaturePrototypeResult.types
new file mode 100644
index 00000000000..1284561880a
--- /dev/null
+++ b/tests/baselines/reference/intersectionWithConstructSignaturePrototypeResult.types
@@ -0,0 +1,34 @@
+//// [tests/cases/compiler/intersectionWithConstructSignaturePrototypeResult.ts] ////
+
+=== intersectionWithConstructSignaturePrototypeResult.ts ===
+declare class EmberObject {}
+>EmberObject : EmberObject
+
+type PersonType = Readonly<typeof EmberObject> &
+>PersonType : Readonly<typeof EmberObject> & (new (properties?: object) => {    firstName: string;    lastName: string;} & EmberObject) & (new (...args: any[]) => {    firstName: string;    lastName: string;} & EmberObject)
+>EmberObject : typeof EmberObject
+
+  (new (properties?: object) => {
+>properties : object | undefined
+
+    firstName: string;
+>firstName : string
+
+    lastName: string;
+>lastName : string
+
+  } & EmberObject) &
+  (new (...args: any[]) => {
+>args : any[]
+
+    firstName: string;
+>firstName : string
+
+    lastName: string;
+>lastName : string
+
+  } & EmberObject);
+
+type PersonPrototype = PersonType["prototype"];
+>PersonPrototype : EmberObject
+
diff --git a/tests/baselines/reference/mappedTypeAsClauses.types b/tests/baselines/reference/mappedTypeAsClauses.types
index 00323af7598..f9d426c0e8f 100644
--- a/tests/baselines/reference/mappedTypeAsClauses.types
+++ b/tests/baselines/reference/mappedTypeAsClauses.types
@@ -35,10 +35,10 @@ type TP1 = TypeFromDefs<{ name: 'a', type: string } | { name: 'b', type: number
 // No array or tuple type mapping when 'as N' clause present
 
 type TA1 = Getters<string[]>;
->TA1 : { getConcat: () => { (...items: ConcatArray<string>[]): string[]; (...items: (string | ConcatArray<string>)[]): string[]; }; getIndexOf: () => (searchElement: string, fromIndex?: number | undefined) => number; getLastIndexOf: () => (searchElement: string, fromIndex?: number | undefined) => number; getSlice: () => (start?: number | undefined, end?: number | undefined) => string[]; getLength: () => number; getToString: () => () => string; getToLocaleString: () => () => string; getPop: () => () => string | undefined; getPush: () => (...items: string[]) => number; getJoin: () => (separator?: string | undefined) => string; getReverse: () => () => string[]; getShift: () => () => string | undefined; getSort: () => (compareFn?: ((a: string, b: string) => number) | undefined) => string[]; getSplice: () => { (start: number, deleteCount?: number | undefined): string[]; (start: number, deleteCount: number, ...items: string[]): string[]; }; getUnshift: () => (...items: string[]) => number; getEvery: () => { <S extends string>(predicate: (value: string, index: number, array: string[]) => value is S, thisArg?: any): this is S[]; (predicate: (value: string, index: number, array: string[]) => unknown, thisArg?: any): boolean; }; getSome: () => (predicate: (value: string, index: number, array: string[]) => unknown, thisArg?: any) => boolean; getForEach: () => (callbackfn: (value: string, index: number, array: string[]) => void, thisArg?: any) => void; getMap: () => <U>(callbackfn: (value: string, index: number, array: string[]) => U, thisArg?: any) => U[]; getFilter: () => { <S_1 extends string>(predicate: (value: string, index: number, array: string[]) => value is S_1, thisArg?: any): S_1[]; (predicate: (value: string, index: number, array: string[]) => unknown, thisArg?: any): string[]; }; getReduce: () => { (callbackfn: (previousValue: string, currentValue: string, currentIndex: number, array: string[]) => string): string; (callbackfn: (previousValue: string, currentValue: string, currentIndex: number, array: string[]) => string, initialValue: string): string; <U_1>(callbackfn: (previousValue: U_1, currentValue: string, currentIndex: number, array: string[]) => U_1, initialValue: U_1): U_1; }; getReduceRight: () => { (callbackfn: (previousValue: string, currentValue: string, currentIndex: number, array: string[]) => string): string; (callbackfn: (previousValue: string, currentValue: string, currentIndex: number, array: string[]) => string, initialValue: string): string; <U_2>(callbackfn: (previousValue: U_2, currentValue: string, currentIndex: number, array: string[]) => U_2, initialValue: U_2): U_2; }; }
+>TA1 : { getConcat: () => { (...items: ConcatArray<string>[]): string[]; (...items: (string | ConcatArray<string>)[]): string[]; }; getIndexOf: () => (searchElement: string, fromIndex?: number | undefined) => number; getLastIndexOf: () => (searchElement: string, fromIndex?: number | undefined) => number; getSlice: () => (start?: number | undefined, end?: number | undefined) => string[]; getLength: () => number; getToLocaleString: () => () => string; getToString: () => () => string; getPop: () => () => string | undefined; getPush: () => (...items: string[]) => number; getJoin: () => (separator?: string | undefined) => string; getReverse: () => () => string[]; getShift: () => () => string | undefined; getSort: () => (compareFn?: ((a: string, b: string) => number) | undefined) => string[]; getSplice: () => { (start: number, deleteCount?: number | undefined): string[]; (start: number, deleteCount: number, ...items: string[]): string[]; }; getUnshift: () => (...items: string[]) => number; getEvery: () => { <S extends string>(predicate: (value: string, index: number, array: string[]) => value is S, thisArg?: any): this is S[]; (predicate: (value: string, index: number, array: string[]) => unknown, thisArg?: any): boolean; }; getSome: () => (predicate: (value: string, index: number, array: string[]) => unknown, thisArg?: any) => boolean; getForEach: () => (callbackfn: (value: string, index: number, array: string[]) => void, thisArg?: any) => void; getMap: () => <U>(callbackfn: (value: string, index: number, array: string[]) => U, thisArg?: any) => U[]; getFilter: () => { <S_1 extends string>(predicate: (value: string, index: number, array: string[]) => value is S_1, thisArg?: any): S_1[]; (predicate: (value: string, index: number, array: string[]) => unknown, thisArg?: any): string[]; }; getReduce: () => { (callbackfn: (previousValue: string, currentValue: string, currentIndex: number, array: string[]) => string): string; (callbackfn: (previousValue: string, currentValue: string, currentIndex: number, array: string[]) => string, initialValue: string): string; <U_1>(callbackfn: (previousValue: U_1, currentValue: string, currentIndex: number, array: string[]) => U_1, initialValue: U_1): U_1; }; getReduceRight: () => { (callbackfn: (previousValue: string, currentValue: string, currentIndex: number, array: string[]) => string): string; (callbackfn: (previousValue: string, currentValue: string, currentIndex: number, array: string[]) => string, initialValue: string): string; <U_2>(callbackfn: (previousValue: U_2, currentValue: string, currentIndex: number, array: string[]) => U_2, initialValue: U_2): U_2; }; }
 
 type TA2 = Getters<[number, boolean]>;
->TA2 : { getConcat: () => { (...items: ConcatArray<number | boolean>[]): (number | boolean)[]; (...items: (number | boolean | ConcatArray<number | boolean>)[]): (number | boolean)[]; }; getIndexOf: () => (searchElement: number | boolean, fromIndex?: number | undefined) => number; getLastIndexOf: () => (searchElement: number | boolean, fromIndex?: number | undefined) => number; getSlice: () => (start?: number | undefined, end?: number | undefined) => (number | boolean)[]; getLength: () => 2; getToString: () => () => string; getToLocaleString: () => () => string; getPop: () => () => number | boolean | undefined; getPush: () => (...items: (number | boolean)[]) => number; getJoin: () => (separator?: string | undefined) => string; getReverse: () => () => (number | boolean)[]; getShift: () => () => number | boolean | undefined; getSort: () => (compareFn?: ((a: number | boolean, b: number | boolean) => number) | undefined) => [number, boolean]; getSplice: () => { (start: number, deleteCount?: number | undefined): (number | boolean)[]; (start: number, deleteCount: number, ...items: (number | boolean)[]): (number | boolean)[]; }; getUnshift: () => (...items: (number | boolean)[]) => number; getEvery: () => { <S extends number | boolean>(predicate: (value: number | boolean, index: number, array: (number | boolean)[]) => value is S, thisArg?: any): this is S[]; (predicate: (value: number | boolean, index: number, array: (number | boolean)[]) => unknown, thisArg?: any): boolean; }; getSome: () => (predicate: (value: number | boolean, index: number, array: (number | boolean)[]) => unknown, thisArg?: any) => boolean; getForEach: () => (callbackfn: (value: number | boolean, index: number, array: (number | boolean)[]) => void, thisArg?: any) => void; getMap: () => <U>(callbackfn: (value: number | boolean, index: number, array: (number | boolean)[]) => U, thisArg?: any) => U[]; getFilter: () => { <S_1 extends number | boolean>(predicate: (value: number | boolean, index: number, array: (number | boolean)[]) => value is S_1, thisArg?: any): S_1[]; (predicate: (value: number | boolean, index: number, array: (number | boolean)[]) => unknown, thisArg?: any): (number | boolean)[]; }; getReduce: () => { (callbackfn: (previousValue: number | boolean, currentValue: number | boolean, currentIndex: number, array: (number | boolean)[]) => number | boolean): number | boolean; (callbackfn: (previousValue: number | boolean, currentValue: number | boolean, currentIndex: number, array: (number | boolean)[]) => number | boolean, initialValue: number | boolean): number | boolean; <U_1>(callbackfn: (previousValue: U_1, currentValue: number | boolean, currentIndex: number, array: (number | boolean)[]) => U_1, initialValue: U_1): U_1; }; getReduceRight: () => { (callbackfn: (previousValue: number | boolean, currentValue: number | boolean, currentIndex: number, array: (number | boolean)[]) => number | boolean): number | boolean; (callbackfn: (previousValue: number | boolean, currentValue: number | boolean, currentIndex: number, array: (number | boolean)[]) => number | boolean, initialValue: number | boolean): number | boolean; <U_2>(callbackfn: (previousValue: U_2, currentValue: number | boolean, currentIndex: number, array: (number | boolean)[]) => U_2, initialValue: U_2): U_2; }; get0: () => number; get1: () => boolean; }
+>TA2 : { getConcat: () => { (...items: ConcatArray<number | boolean>[]): (number | boolean)[]; (...items: (number | boolean | ConcatArray<number | boolean>)[]): (number | boolean)[]; }; getIndexOf: () => (searchElement: number | boolean, fromIndex?: number | undefined) => number; getLastIndexOf: () => (searchElement: number | boolean, fromIndex?: number | undefined) => number; getSlice: () => (start?: number | undefined, end?: number | undefined) => (number | boolean)[]; getLength: () => 2; getToLocaleString: () => () => string; getToString: () => () => string; getPop: () => () => number | boolean | undefined; getPush: () => (...items: (number | boolean)[]) => number; getJoin: () => (separator?: string | undefined) => string; getReverse: () => () => (number | boolean)[]; getShift: () => () => number | boolean | undefined; getSort: () => (compareFn?: ((a: number | boolean, b: number | boolean) => number) | undefined) => [number, boolean]; getSplice: () => { (start: number, deleteCount?: number | undefined): (number | boolean)[]; (start: number, deleteCount: number, ...items: (number | boolean)[]): (number | boolean)[]; }; getUnshift: () => (...items: (number | boolean)[]) => number; getEvery: () => { <S extends number | boolean>(predicate: (value: number | boolean, index: number, array: (number | boolean)[]) => value is S, thisArg?: any): this is S[]; (predicate: (value: number | boolean, index: number, array: (number | boolean)[]) => unknown, thisArg?: any): boolean; }; getSome: () => (predicate: (value: number | boolean, index: number, array: (number | boolean)[]) => unknown, thisArg?: any) => boolean; getForEach: () => (callbackfn: (value: number | boolean, index: number, array: (number | boolean)[]) => void, thisArg?: any) => void; getMap: () => <U>(callbackfn: (value: number | boolean, index: number, array: (number | boolean)[]) => U, thisArg?: any) => U[]; getFilter: () => { <S_1 extends number | boolean>(predicate: (value: number | boolean, index: number, array: (number | boolean)[]) => value is S_1, thisArg?: any): S_1[]; (predicate: (value: number | boolean, index: number, array: (number | boolean)[]) => unknown, thisArg?: any): (number | boolean)[]; }; getReduce: () => { (callbackfn: (previousValue: number | boolean, currentValue: number | boolean, currentIndex: number, array: (number | boolean)[]) => number | boolean): number | boolean; (callbackfn: (previousValue: number | boolean, currentValue: number | boolean, currentIndex: number, array: (number | boolean)[]) => number | boolean, initialValue: number | boolean): number | boolean; <U_1>(callbackfn: (previousValue: U_1, currentValue: number | boolean, currentIndex: number, array: (number | boolean)[]) => U_1, initialValue: U_1): U_1; }; getReduceRight: () => { (callbackfn: (previousValue: number | boolean, currentValue: number | boolean, currentIndex: number, array: (number | boolean)[]) => number | boolean): number | boolean; (callbackfn: (previousValue: number | boolean, currentValue: number | boolean, currentIndex: number, array: (number | boolean)[]) => number | boolean, initialValue: number | boolean): number | boolean; <U_2>(callbackfn: (previousValue: U_2, currentValue: number | boolean, currentIndex: number, array: (number | boolean)[]) => U_2, initialValue: U_2): U_2; }; get0: () => number; get1: () => boolean; }
 
 // Filtering using 'as N' clause
 
diff --git a/tests/baselines/reference/uncalledFunctionChecksInConditional2.errors.txt b/tests/baselines/reference/uncalledFunctionChecksInConditional2.errors.txt
index af6aea3676d..54feef1029a 100644
--- a/tests/baselines/reference/uncalledFunctionChecksInConditional2.errors.txt
+++ b/tests/baselines/reference/uncalledFunctionChecksInConditional2.errors.txt
@@ -69,4 +69,16 @@ uncalledFunctionChecksInConditional2.ts(49,5): error TS2774: This condition will
         }
       }
     };
+    
+    let _isMobile: boolean;
+    function isMobile() {
+      if (_isMobile === undefined) {
+        const isMobileMatch =
+          typeof window !== 'undefined' &&
+          window.matchMedia && // no error
+          window.matchMedia('(max-device-width: 680px)');
+        _isMobile = isMobileMatch && isMobileMatch.matches;
+      }
+      return _isMobile;
+    }
     
\ No newline at end of file
diff --git a/tests/baselines/reference/uncalledFunctionChecksInConditional2.js b/tests/baselines/reference/uncalledFunctionChecksInConditional2.js
index cf63e988127..becc23beb1e 100644
--- a/tests/baselines/reference/uncalledFunctionChecksInConditional2.js
+++ b/tests/baselines/reference/uncalledFunctionChecksInConditional2.js
@@ -60,6 +60,18 @@ declare let inBrowser: boolean;
     }
   }
 };
+
+let _isMobile: boolean;
+function isMobile() {
+  if (_isMobile === undefined) {
+    const isMobileMatch =
+      typeof window !== 'undefined' &&
+      window.matchMedia && // no error
+      window.matchMedia('(max-device-width: 680px)');
+    _isMobile = isMobileMatch && isMobileMatch.matches;
+  }
+  return _isMobile;
+}
 
 
 //// [uncalledFunctionChecksInConditional2.js]
@@ -109,3 +121,13 @@ var _a;
     }
 }
 ;
+var _isMobile;
+function isMobile() {
+    if (_isMobile === undefined) {
+        var isMobileMatch = typeof window !== 'undefined' &&
+            window.matchMedia && // no error
+            window.matchMedia('(max-device-width: 680px)');
+        _isMobile = isMobileMatch && isMobileMatch.matches;
+    }
+    return _isMobile;
+}
diff --git a/tests/baselines/reference/uncalledFunctionChecksInConditional2.symbols b/tests/baselines/reference/uncalledFunctionChecksInConditional2.symbols
index 19c500ea8be..a98be45df9f 100644
--- a/tests/baselines/reference/uncalledFunctionChecksInConditional2.symbols
+++ b/tests/baselines/reference/uncalledFunctionChecksInConditional2.symbols
@@ -174,3 +174,40 @@ declare let inBrowser: boolean;
   }
 };
 
+let _isMobile: boolean;
+>_isMobile : Symbol(_isMobile, Decl(uncalledFunctionChecksInConditional2.ts, 60, 3))
+
+function isMobile() {
+>isMobile : Symbol(isMobile, Decl(uncalledFunctionChecksInConditional2.ts, 60, 23))
+
+  if (_isMobile === undefined) {
+>_isMobile : Symbol(_isMobile, Decl(uncalledFunctionChecksInConditional2.ts, 60, 3))
+>undefined : Symbol(undefined)
+
+    const isMobileMatch =
+>isMobileMatch : Symbol(isMobileMatch, Decl(uncalledFunctionChecksInConditional2.ts, 63, 9))
+
+      typeof window !== 'undefined' &&
+>window : Symbol(window, Decl(lib.dom.d.ts, --, --))
+
+      window.matchMedia && // no error
+>window.matchMedia : Symbol(matchMedia, Decl(lib.dom.d.ts, --, --), Decl(lib.dom.d.ts, --, --))
+>window : Symbol(window, Decl(lib.dom.d.ts, --, --))
+>matchMedia : Symbol(matchMedia, Decl(lib.dom.d.ts, --, --), Decl(lib.dom.d.ts, --, --))
+
+      window.matchMedia('(max-device-width: 680px)');
+>window.matchMedia : Symbol(matchMedia, Decl(lib.dom.d.ts, --, --), Decl(lib.dom.d.ts, --, --))
+>window : Symbol(window, Decl(lib.dom.d.ts, --, --))
+>matchMedia : Symbol(matchMedia, Decl(lib.dom.d.ts, --, --), Decl(lib.dom.d.ts, --, --))
+
+    _isMobile = isMobileMatch && isMobileMatch.matches;
+>_isMobile : Symbol(_isMobile, Decl(uncalledFunctionChecksInConditional2.ts, 60, 3))
+>isMobileMatch : Symbol(isMobileMatch, Decl(uncalledFunctionChecksInConditional2.ts, 63, 9))
+>isMobileMatch.matches : Symbol(MediaQueryList.matches, Decl(lib.dom.d.ts, --, --))
+>isMobileMatch : Symbol(isMobileMatch, Decl(uncalledFunctionChecksInConditional2.ts, 63, 9))
+>matches : Symbol(MediaQueryList.matches, Decl(lib.dom.d.ts, --, --))
+  }
+  return _isMobile;
+>_isMobile : Symbol(_isMobile, Decl(uncalledFunctionChecksInConditional2.ts, 60, 3))
+}
+
diff --git a/tests/baselines/reference/uncalledFunctionChecksInConditional2.types b/tests/baselines/reference/uncalledFunctionChecksInConditional2.types
index 60eeef5fb8d..a14c167b9aa 100644
--- a/tests/baselines/reference/uncalledFunctionChecksInConditional2.types
+++ b/tests/baselines/reference/uncalledFunctionChecksInConditional2.types
@@ -215,3 +215,50 @@ declare let inBrowser: boolean;
   }
 };
 
+let _isMobile: boolean;
+>_isMobile : boolean
+
+function isMobile() {
+>isMobile : () => boolean
+
+  if (_isMobile === undefined) {
+>_isMobile === undefined : boolean
+>_isMobile : boolean
+>undefined : undefined
+
+    const isMobileMatch =
+>isMobileMatch : false | MediaQueryList
+
+      typeof window !== 'undefined' &&
+>typeof window !== 'undefined' &&      window.matchMedia && // no error      window.matchMedia('(max-device-width: 680px)') : false | MediaQueryList
+>typeof window !== 'undefined' &&      window.matchMedia : false | (((query: string) => MediaQueryList) & ((query: string) => MediaQueryList))
+>typeof window !== 'undefined' : boolean
+>typeof window : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
+>window : Window & typeof globalThis
+>'undefined' : "undefined"
+
+      window.matchMedia && // no error
+>window.matchMedia : ((query: string) => MediaQueryList) & ((query: string) => MediaQueryList)
+>window : Window & typeof globalThis
+>matchMedia : ((query: string) => MediaQueryList) & ((query: string) => MediaQueryList)
+
+      window.matchMedia('(max-device-width: 680px)');
+>window.matchMedia('(max-device-width: 680px)') : MediaQueryList
+>window.matchMedia : ((query: string) => MediaQueryList) & ((query: string) => MediaQueryList)
+>window : Window & typeof globalThis
+>matchMedia : ((query: string) => MediaQueryList) & ((query: string) => MediaQueryList)
+>'(max-device-width: 680px)' : "(max-device-width: 680px)"
+
+    _isMobile = isMobileMatch && isMobileMatch.matches;
+>_isMobile = isMobileMatch && isMobileMatch.matches : boolean
+>_isMobile : boolean
+>isMobileMatch && isMobileMatch.matches : boolean
+>isMobileMatch : false | MediaQueryList
+>isMobileMatch.matches : boolean
+>isMobileMatch : MediaQueryList
+>matches : boolean
+  }
+  return _isMobile;
+>_isMobile : boolean
+}
+
diff --git a/tests/cases/compiler/intersectionWithConstructSignaturePrototypeResult.ts b/tests/cases/compiler/intersectionWithConstructSignaturePrototypeResult.ts
new file mode 100644
index 00000000000..28eb6c6b956
--- /dev/null
+++ b/tests/cases/compiler/intersectionWithConstructSignaturePrototypeResult.ts
@@ -0,0 +1,16 @@
+// @strict: true
+// @noEmit: true
+
+declare class EmberObject {}
+
+type PersonType = Readonly<typeof EmberObject> &
+  (new (properties?: object) => {
+    firstName: string;
+    lastName: string;
+  } & EmberObject) &
+  (new (...args: any[]) => {
+    firstName: string;
+    lastName: string;
+  } & EmberObject);
+
+type PersonPrototype = PersonType["prototype"];
diff --git a/tests/cases/compiler/uncalledFunctionChecksInConditional2.ts b/tests/cases/compiler/uncalledFunctionChecksInConditional2.ts
index dc75f72cec4..425584ba171 100644
--- a/tests/cases/compiler/uncalledFunctionChecksInConditional2.ts
+++ b/tests/cases/compiler/uncalledFunctionChecksInConditional2.ts
@@ -59,3 +59,15 @@ declare let inBrowser: boolean;
     }
   }
 };
+
+let _isMobile: boolean;
+function isMobile() {
+  if (_isMobile === undefined) {
+    const isMobileMatch =
+      typeof window !== 'undefined' &&
+      window.matchMedia && // no error
+      window.matchMedia('(max-device-width: 680px)');
+    _isMobile = isMobileMatch && isMobileMatch.matches;
+  }
+  return _isMobile;
+}
diff --git a/tests/cases/conformance/types/typeRelationships/assignmentCompatibility/intersectionIncludingPropFromGlobalAugmentation.ts b/tests/cases/conformance/types/typeRelationships/assignmentCompatibility/intersectionIncludingPropFromGlobalAugmentation.ts
new file mode 100644
index 00000000000..00a17068d9b
--- /dev/null
+++ b/tests/cases/conformance/types/typeRelationships/assignmentCompatibility/intersectionIncludingPropFromGlobalAugmentation.ts
@@ -0,0 +1,14 @@
+// @strict: true
+// @noEmit: true
+
+// repro from https://github.com/microsoft/TypeScript/issues/54345
+
+interface Test1 { toString: null | 'string'; }
+type Test2 = Test1 & { optional?: unknown };
+declare const source: Test1;
+const target: Test2 = { ...source };
+
+const toString = target.toString;
+const hasOwn = target.hasOwnProperty; // not an own member but it should still be accessible
+
+export {}