diff --git a/baselines/dom.generated.d.ts b/baselines/dom.generated.d.ts
index 74c47ae0d..0cd1defdd 100644
--- a/baselines/dom.generated.d.ts
+++ b/baselines/dom.generated.d.ts
@@ -38143,13 +38143,13 @@ interface URL {
 
 declare var URL: {
     prototype: URL;
-    new(url: string | URL, base?: string | URL): URL;
+    new(url: string | URL | Location, base?: string | URL | Location): URL;
     /**
      * The **`URL.canParse()`** static method of the URL interface returns a boolean indicating whether or not an absolute URL, or a relative URL combined with a base URL, are parsable and valid.
      *
      * [MDN Reference](https://developer.mozilla.org/docs/Web/API/URL/canParse_static)
      */
-    canParse(url: string | URL, base?: string | URL): boolean;
+    canParse(url: string | URL | Location, base?: string | URL | Location): boolean;
     /**
      * The **`createObjectURL()`** static method of the URL interface creates a string containing a blob URL pointing to the object given in the parameter.
      *
@@ -38161,7 +38161,7 @@ declare var URL: {
      *
      * [MDN Reference](https://developer.mozilla.org/docs/Web/API/URL/parse_static)
      */
-    parse(url: string | URL, base?: string | URL): URL | null;
+    parse(url: string | URL | Location, base?: string | URL | Location): URL | null;
     /**
      * The **`revokeObjectURL()`** static method of the URL interface releases an existing object URL which was previously created by calling URL.createObjectURL().
      *
@@ -42865,8 +42865,8 @@ interface XMLHttpRequest extends XMLHttpRequestEventTarget {
      *
      * [MDN Reference](https://developer.mozilla.org/docs/Web/API/XMLHttpRequest/open)
      */
-    open(method: string, url: string | URL): void;
-    open(method: string, url: string | URL, async: boolean, username?: string | null, password?: string | null): void;
+    open(method: string, url: string | URL | Location): void;
+    open(method: string, url: string | URL | Location, async: boolean, username?: string | null, password?: string | null): void;
     /**
      * The XMLHttpRequest method **`overrideMimeType()`** specifies a MIME type other than the one provided by the server to be used instead when interpreting the data being transferred in a request.
      *
diff --git a/baselines/ts5.5/dom.generated.d.ts b/baselines/ts5.5/dom.generated.d.ts
index 61e3f2db2..0c8c31d5c 100644
--- a/baselines/ts5.5/dom.generated.d.ts
+++ b/baselines/ts5.5/dom.generated.d.ts
@@ -38117,13 +38117,13 @@ interface URL {
 
 declare var URL: {
     prototype: URL;
-    new(url: string | URL, base?: string | URL): URL;
+    new(url: string | URL | Location, base?: string | URL | Location): URL;
     /**
      * The **`URL.canParse()`** static method of the URL interface returns a boolean indicating whether or not an absolute URL, or a relative URL combined with a base URL, are parsable and valid.
      *
      * [MDN Reference](https://developer.mozilla.org/docs/Web/API/URL/canParse_static)
      */
-    canParse(url: string | URL, base?: string | URL): boolean;
+    canParse(url: string | URL | Location, base?: string | URL | Location): boolean;
     /**
      * The **`createObjectURL()`** static method of the URL interface creates a string containing a blob URL pointing to the object given in the parameter.
      *
@@ -38135,7 +38135,7 @@ declare var URL: {
      *
      * [MDN Reference](https://developer.mozilla.org/docs/Web/API/URL/parse_static)
      */
-    parse(url: string | URL, base?: string | URL): URL | null;
+    parse(url: string | URL | Location, base?: string | URL | Location): URL | null;
     /**
      * The **`revokeObjectURL()`** static method of the URL interface releases an existing object URL which was previously created by calling URL.createObjectURL().
      *
@@ -42839,8 +42839,8 @@ interface XMLHttpRequest extends XMLHttpRequestEventTarget {
      *
      * [MDN Reference](https://developer.mozilla.org/docs/Web/API/XMLHttpRequest/open)
      */
-    open(method: string, url: string | URL): void;
-    open(method: string, url: string | URL, async: boolean, username?: string | null, password?: string | null): void;
+    open(method: string, url: string | URL | Location): void;
+    open(method: string, url: string | URL | Location, async: boolean, username?: string | null, password?: string | null): void;
     /**
      * The XMLHttpRequest method **`overrideMimeType()`** specifies a MIME type other than the one provided by the server to be used instead when interpreting the data being transferred in a request.
      *
diff --git a/baselines/ts5.6/dom.generated.d.ts b/baselines/ts5.6/dom.generated.d.ts
index ec099f4f8..97005a267 100644
--- a/baselines/ts5.6/dom.generated.d.ts
+++ b/baselines/ts5.6/dom.generated.d.ts
@@ -38140,13 +38140,13 @@ interface URL {
 
 declare var URL: {
     prototype: URL;
-    new(url: string | URL, base?: string | URL): URL;
+    new(url: string | URL | Location, base?: string | URL | Location): URL;
     /**
      * The **`URL.canParse()`** static method of the URL interface returns a boolean indicating whether or not an absolute URL, or a relative URL combined with a base URL, are parsable and valid.
      *
      * [MDN Reference](https://developer.mozilla.org/docs/Web/API/URL/canParse_static)
      */
-    canParse(url: string | URL, base?: string | URL): boolean;
+    canParse(url: string | URL | Location, base?: string | URL | Location): boolean;
     /**
      * The **`createObjectURL()`** static method of the URL interface creates a string containing a blob URL pointing to the object given in the parameter.
      *
@@ -38158,7 +38158,7 @@ declare var URL: {
      *
      * [MDN Reference](https://developer.mozilla.org/docs/Web/API/URL/parse_static)
      */
-    parse(url: string | URL, base?: string | URL): URL | null;
+    parse(url: string | URL | Location, base?: string | URL | Location): URL | null;
     /**
      * The **`revokeObjectURL()`** static method of the URL interface releases an existing object URL which was previously created by calling URL.createObjectURL().
      *
@@ -42862,8 +42862,8 @@ interface XMLHttpRequest extends XMLHttpRequestEventTarget {
      *
      * [MDN Reference](https://developer.mozilla.org/docs/Web/API/XMLHttpRequest/open)
      */
-    open(method: string, url: string | URL): void;
-    open(method: string, url: string | URL, async: boolean, username?: string | null, password?: string | null): void;
+    open(method: string, url: string | URL | Location): void;
+    open(method: string, url: string | URL | Location, async: boolean, username?: string | null, password?: string | null): void;
     /**
      * The XMLHttpRequest method **`overrideMimeType()`** specifies a MIME type other than the one provided by the server to be used instead when interpreting the data being transferred in a request.
      *
diff --git a/baselines/ts5.9/dom.generated.d.ts b/baselines/ts5.9/dom.generated.d.ts
index c7be83a7a..40c5cc990 100644
--- a/baselines/ts5.9/dom.generated.d.ts
+++ b/baselines/ts5.9/dom.generated.d.ts
@@ -38140,13 +38140,13 @@ interface URL {
 
 declare var URL: {
     prototype: URL;
-    new(url: string | URL, base?: string | URL): URL;
+    new(url: string | URL | Location, base?: string | URL | Location): URL;
     /**
      * The **`URL.canParse()`** static method of the URL interface returns a boolean indicating whether or not an absolute URL, or a relative URL combined with a base URL, are parsable and valid.
      *
      * [MDN Reference](https://developer.mozilla.org/docs/Web/API/URL/canParse_static)
      */
-    canParse(url: string | URL, base?: string | URL): boolean;
+    canParse(url: string | URL | Location, base?: string | URL | Location): boolean;
     /**
      * The **`createObjectURL()`** static method of the URL interface creates a string containing a blob URL pointing to the object given in the parameter.
      *
@@ -38158,7 +38158,7 @@ declare var URL: {
      *
      * [MDN Reference](https://developer.mozilla.org/docs/Web/API/URL/parse_static)
      */
-    parse(url: string | URL, base?: string | URL): URL | null;
+    parse(url: string | URL | Location, base?: string | URL | Location): URL | null;
     /**
      * The **`revokeObjectURL()`** static method of the URL interface releases an existing object URL which was previously created by calling URL.createObjectURL().
      *
@@ -42862,8 +42862,8 @@ interface XMLHttpRequest extends XMLHttpRequestEventTarget {
      *
      * [MDN Reference](https://developer.mozilla.org/docs/Web/API/XMLHttpRequest/open)
      */
-    open(method: string, url: string | URL): void;
-    open(method: string, url: string | URL, async: boolean, username?: string | null, password?: string | null): void;
+    open(method: string, url: string | URL | Location): void;
+    open(method: string, url: string | URL | Location, async: boolean, username?: string | null, password?: string | null): void;
     /**
      * The XMLHttpRequest method **`overrideMimeType()`** specifies a MIME type other than the one provided by the server to be used instead when interpreting the data being transferred in a request.
      *
diff --git a/inputfiles/overridingTypes.jsonc b/inputfiles/overridingTypes.jsonc
index b20f538ba..8dabe6754 100644
--- a/inputfiles/overridingTypes.jsonc
+++ b/inputfiles/overridingTypes.jsonc
@@ -1545,48 +1545,6 @@
                     }
                 }
             },
-            "URL": {
-                "constructor": {
-                    "signature": {
-                        "0": {
-                            "param": [
-                                {
-                                    "name": "base",
-                                    "additionalTypes": ["URL"]
-                                }
-                            ]
-                        }
-                    }
-                },
-                "methods": {
-                    "method": {
-                        "canParse": {
-                            "signature": {
-                                "0": {
-                                    "param": [
-                                        {
-                                            "name": "base",
-                                            "additionalTypes": ["URL"]
-                                        }
-                                    ]
-                                }
-                            }
-                        },
-                        "parse": {
-                            "signature": {
-                                "0": {
-                                    "param": [
-                                        {
-                                            "name": "base",
-                                            "additionalTypes": ["URL"]
-                                        }
-                                    ]
-                                }
-                            }
-                        }
-                    }
-                }
-            },
             "Client": {
                 "properties": {
                     "property": {
diff --git a/inputfiles/patches/url.kdl b/inputfiles/patches/url.kdl
index b4fbeb195..0bcdd93ff 100644
--- a/inputfiles/patches/url.kdl
+++ b/inputfiles/patches/url.kdl
@@ -5,3 +5,30 @@ interface URLSearchParams {
         }
     }
 }
+
+interface URL {
+    constructor signatureIndex=0 {
+        param url {
+            additionalTypes URL Location
+        }
+        param base {
+            additionalTypes URL Location
+        }
+    }
+    method canParse signatureIndex=0 {
+        param url {
+            additionalTypes URL Location
+        }
+        param base {
+            additionalTypes URL Location
+        }
+    }
+    method parse signatureIndex=0 {
+        param url {
+            additionalTypes URL Location
+        }
+        param base {
+            additionalTypes URL Location
+        }
+    }
+}
diff --git a/inputfiles/patches/xhr.kdl b/inputfiles/patches/xhr.kdl
new file mode 100644
index 000000000..49ee3768a
--- /dev/null
+++ b/inputfiles/patches/xhr.kdl
@@ -0,0 +1,12 @@
+interface XMLHttpRequest {
+    method open signatureIndex=0 {
+        param url {
+            additionalTypes URL Location
+        }
+    }
+    method open signatureIndex=1 {
+        param url {
+            additionalTypes URL Location
+        }
+    }
+}
diff --git a/src/build/emitter.ts b/src/build/emitter.ts
index 31e43749f..d9a33a56a 100644
--- a/src/build/emitter.ts
+++ b/src/build/emitter.ts
@@ -429,7 +429,11 @@ export function emitWebIdl(
           typeof obj.type === "string"
             ? [{ ...obj, additionalTypes: undefined }]
             : obj.type;
-        types.push(...(obj.additionalTypes ?? []).map((t) => ({ type: t })));
+        types.push(
+          ...(obj.additionalTypes ?? [])
+            .filter((t) => isKnownType(t))
+            .map((t) => ({ type: t })),
+        );
 
         // propagate `any`
         const converted = types.map((t) =>
@@ -520,6 +524,18 @@ export function emitWebIdl(
     throw new Error("Unknown DOM type: " + objDomType);
   }
 
+  function isKnownType(type: string) {
+    return (
+      baseTypeConversionMap.has(type) ||
+      allInterfacesMap[type] ||
+      allLegacyWindowAliases.includes(type) ||
+      allCallbackFunctionsMap[type] ||
+      allDictionariesMap[type] ||
+      allEnumsMap[type] ||
+      allTypedefsMap[type]
+    );
+  }
+
   function makeNullable(originalType: string) {
     switch (originalType) {
       case "any":
@@ -795,7 +811,9 @@ export function emitWebIdl(
       p = resolvePromise(p);
       if (acceptsUrl(p)) {
         p = { ...p, additionalTypes: [...(p.additionalTypes ?? [])] };
-        p.additionalTypes!.push("URL");
+        if (!p.additionalTypes!.includes("URL")) {
+          p.additionalTypes!.push("URL");
+        }
       }
       const pType = convertDomTypeToTsType(p);
 
diff --git a/src/build/expose.ts b/src/build/expose.ts
index 4c0c023c0..a60d45f3d 100644
--- a/src/build/expose.ts
+++ b/src/build/expose.ts
@@ -177,6 +177,9 @@ function deepFilterUnexposedTypes(
   unexposedTypes: Set<string>,
 ) {
   return deepClone(webidl, (o) => {
+    if (o.additionalTypes) {
+      return filterUnexposedType(o, unexposedTypes);
+    }
     if (Array.isArray(o.type)) {
       return {
         ...o,
@@ -237,13 +240,35 @@ function filterUnexposedType<T extends Browser.Typed>(
       unexposedTypes,
     );
     if (filteredUnion.length) {
-      return { ...type, type: flattenType(filteredUnion) };
+      return {
+        ...type,
+        type: flattenType(filteredUnion),
+        additionalTypes: filterAdditionalTypes(
+          type.additionalTypes,
+          unexposedTypes,
+        ),
+      };
     }
-  } else if (type.overrideType || !unexposedTypes.has(type.type)) {
-    return type;
+  } else if (!type.overrideType && unexposedTypes.has(type.type)) {
+    return;
+  } else {
+    const additionalTypes = filterAdditionalTypes(
+      type.additionalTypes,
+      unexposedTypes,
+    );
+    return additionalTypes ? { ...type, additionalTypes } : type;
   }
 }
 
+function filterAdditionalTypes(
+  additionalTypes: string[] | undefined,
+  unexposedTypes: Set<string>,
+) {
+  return additionalTypes?.filter(
+    (additionalType) => !unexposedTypes.has(additionalType),
+  );
+}
+
 function filterUnexposedTypeFromUnion(
   union: Browser.Typed[],
   unexposedTypes: Set<string>,