diff --git a/baselines/dom.generated.d.ts b/baselines/dom.generated.d.ts
index 2cb8edcbc..3d0a0f27a 100644
--- a/baselines/dom.generated.d.ts
+++ b/baselines/dom.generated.d.ts
@@ -2674,6 +2674,7 @@ interface WebTransportHash {
 interface WebTransportOptions {
     allowPooling?: boolean;
     congestionControl?: WebTransportCongestionControl;
+    protocols?: string[];
     requireUnreliable?: boolean;
     serverCertificateHashes?: WebTransportHash[];
 }
diff --git a/baselines/serviceworker.generated.d.ts b/baselines/serviceworker.generated.d.ts
index f2ecfa948..196faf54f 100644
--- a/baselines/serviceworker.generated.d.ts
+++ b/baselines/serviceworker.generated.d.ts
@@ -858,6 +858,7 @@ interface WebTransportHash {
 interface WebTransportOptions {
     allowPooling?: boolean;
     congestionControl?: WebTransportCongestionControl;
+    protocols?: string[];
     requireUnreliable?: boolean;
     serverCertificateHashes?: WebTransportHash[];
 }
diff --git a/baselines/sharedworker.generated.d.ts b/baselines/sharedworker.generated.d.ts
index 959470cca..223d63be5 100644
--- a/baselines/sharedworker.generated.d.ts
+++ b/baselines/sharedworker.generated.d.ts
@@ -788,6 +788,7 @@ interface WebTransportHash {
 interface WebTransportOptions {
     allowPooling?: boolean;
     congestionControl?: WebTransportCongestionControl;
+    protocols?: string[];
     requireUnreliable?: boolean;
     serverCertificateHashes?: WebTransportHash[];
 }
diff --git a/baselines/ts5.5/dom.generated.d.ts b/baselines/ts5.5/dom.generated.d.ts
index d907cc610..3882d29ba 100644
--- a/baselines/ts5.5/dom.generated.d.ts
+++ b/baselines/ts5.5/dom.generated.d.ts
@@ -2671,6 +2671,7 @@ interface WebTransportHash {
 interface WebTransportOptions {
     allowPooling?: boolean;
     congestionControl?: WebTransportCongestionControl;
+    protocols?: string[];
     requireUnreliable?: boolean;
     serverCertificateHashes?: WebTransportHash[];
 }
diff --git a/baselines/ts5.5/serviceworker.generated.d.ts b/baselines/ts5.5/serviceworker.generated.d.ts
index 8d4fa0283..f394df893 100644
--- a/baselines/ts5.5/serviceworker.generated.d.ts
+++ b/baselines/ts5.5/serviceworker.generated.d.ts
@@ -855,6 +855,7 @@ interface WebTransportHash {
 interface WebTransportOptions {
     allowPooling?: boolean;
     congestionControl?: WebTransportCongestionControl;
+    protocols?: string[];
     requireUnreliable?: boolean;
     serverCertificateHashes?: WebTransportHash[];
 }
diff --git a/baselines/ts5.5/sharedworker.generated.d.ts b/baselines/ts5.5/sharedworker.generated.d.ts
index 032c3340e..54e467b46 100644
--- a/baselines/ts5.5/sharedworker.generated.d.ts
+++ b/baselines/ts5.5/sharedworker.generated.d.ts
@@ -785,6 +785,7 @@ interface WebTransportHash {
 interface WebTransportOptions {
     allowPooling?: boolean;
     congestionControl?: WebTransportCongestionControl;
+    protocols?: string[];
     requireUnreliable?: boolean;
     serverCertificateHashes?: WebTransportHash[];
 }
diff --git a/baselines/ts5.5/webworker.generated.d.ts b/baselines/ts5.5/webworker.generated.d.ts
index 175c2d21b..929090d4a 100644
--- a/baselines/ts5.5/webworker.generated.d.ts
+++ b/baselines/ts5.5/webworker.generated.d.ts
@@ -1093,6 +1093,7 @@ interface WebTransportHash {
 interface WebTransportOptions {
     allowPooling?: boolean;
     congestionControl?: WebTransportCongestionControl;
+    protocols?: string[];
     requireUnreliable?: boolean;
     serverCertificateHashes?: WebTransportHash[];
 }
diff --git a/baselines/ts5.6/dom.generated.d.ts b/baselines/ts5.6/dom.generated.d.ts
index 3293ad1fa..00cbe6142 100644
--- a/baselines/ts5.6/dom.generated.d.ts
+++ b/baselines/ts5.6/dom.generated.d.ts
@@ -2671,6 +2671,7 @@ interface WebTransportHash {
 interface WebTransportOptions {
     allowPooling?: boolean;
     congestionControl?: WebTransportCongestionControl;
+    protocols?: string[];
     requireUnreliable?: boolean;
     serverCertificateHashes?: WebTransportHash[];
 }
diff --git a/baselines/ts5.6/serviceworker.generated.d.ts b/baselines/ts5.6/serviceworker.generated.d.ts
index 8d4fa0283..f394df893 100644
--- a/baselines/ts5.6/serviceworker.generated.d.ts
+++ b/baselines/ts5.6/serviceworker.generated.d.ts
@@ -855,6 +855,7 @@ interface WebTransportHash {
 interface WebTransportOptions {
     allowPooling?: boolean;
     congestionControl?: WebTransportCongestionControl;
+    protocols?: string[];
     requireUnreliable?: boolean;
     serverCertificateHashes?: WebTransportHash[];
 }
diff --git a/baselines/ts5.6/sharedworker.generated.d.ts b/baselines/ts5.6/sharedworker.generated.d.ts
index 032c3340e..54e467b46 100644
--- a/baselines/ts5.6/sharedworker.generated.d.ts
+++ b/baselines/ts5.6/sharedworker.generated.d.ts
@@ -785,6 +785,7 @@ interface WebTransportHash {
 interface WebTransportOptions {
     allowPooling?: boolean;
     congestionControl?: WebTransportCongestionControl;
+    protocols?: string[];
     requireUnreliable?: boolean;
     serverCertificateHashes?: WebTransportHash[];
 }
diff --git a/baselines/ts5.6/webworker.generated.d.ts b/baselines/ts5.6/webworker.generated.d.ts
index 175c2d21b..929090d4a 100644
--- a/baselines/ts5.6/webworker.generated.d.ts
+++ b/baselines/ts5.6/webworker.generated.d.ts
@@ -1093,6 +1093,7 @@ interface WebTransportHash {
 interface WebTransportOptions {
     allowPooling?: boolean;
     congestionControl?: WebTransportCongestionControl;
+    protocols?: string[];
     requireUnreliable?: boolean;
     serverCertificateHashes?: WebTransportHash[];
 }
diff --git a/baselines/ts5.9/dom.generated.d.ts b/baselines/ts5.9/dom.generated.d.ts
index 440c09798..028e33758 100644
--- a/baselines/ts5.9/dom.generated.d.ts
+++ b/baselines/ts5.9/dom.generated.d.ts
@@ -2671,6 +2671,7 @@ interface WebTransportHash {
 interface WebTransportOptions {
     allowPooling?: boolean;
     congestionControl?: WebTransportCongestionControl;
+    protocols?: string[];
     requireUnreliable?: boolean;
     serverCertificateHashes?: WebTransportHash[];
 }
diff --git a/baselines/ts5.9/serviceworker.generated.d.ts b/baselines/ts5.9/serviceworker.generated.d.ts
index c2dd725cf..67ea0438c 100644
--- a/baselines/ts5.9/serviceworker.generated.d.ts
+++ b/baselines/ts5.9/serviceworker.generated.d.ts
@@ -855,6 +855,7 @@ interface WebTransportHash {
 interface WebTransportOptions {
     allowPooling?: boolean;
     congestionControl?: WebTransportCongestionControl;
+    protocols?: string[];
     requireUnreliable?: boolean;
     serverCertificateHashes?: WebTransportHash[];
 }
diff --git a/baselines/ts5.9/sharedworker.generated.d.ts b/baselines/ts5.9/sharedworker.generated.d.ts
index 4ced8a11d..b6e7045fd 100644
--- a/baselines/ts5.9/sharedworker.generated.d.ts
+++ b/baselines/ts5.9/sharedworker.generated.d.ts
@@ -785,6 +785,7 @@ interface WebTransportHash {
 interface WebTransportOptions {
     allowPooling?: boolean;
     congestionControl?: WebTransportCongestionControl;
+    protocols?: string[];
     requireUnreliable?: boolean;
     serverCertificateHashes?: WebTransportHash[];
 }
diff --git a/baselines/ts5.9/webworker.generated.d.ts b/baselines/ts5.9/webworker.generated.d.ts
index 15d18d9f3..22c301762 100644
--- a/baselines/ts5.9/webworker.generated.d.ts
+++ b/baselines/ts5.9/webworker.generated.d.ts
@@ -1093,6 +1093,7 @@ interface WebTransportHash {
 interface WebTransportOptions {
     allowPooling?: boolean;
     congestionControl?: WebTransportCongestionControl;
+    protocols?: string[];
     requireUnreliable?: boolean;
     serverCertificateHashes?: WebTransportHash[];
 }
diff --git a/baselines/webworker.generated.d.ts b/baselines/webworker.generated.d.ts
index 8de3574a8..c15559c46 100644
--- a/baselines/webworker.generated.d.ts
+++ b/baselines/webworker.generated.d.ts
@@ -1096,6 +1096,7 @@ interface WebTransportHash {
 interface WebTransportOptions {
     allowPooling?: boolean;
     congestionControl?: WebTransportCongestionControl;
+    protocols?: string[];
     requireUnreliable?: boolean;
     serverCertificateHashes?: WebTransportHash[];
 }
diff --git a/inputfiles/patches/webtransport.kdl b/inputfiles/patches/webtransport.kdl
new file mode 100644
index 000000000..246db7097
--- /dev/null
+++ b/inputfiles/patches/webtransport.kdl
@@ -0,0 +1,9 @@
+removals {
+  dictionary WebTransportOptions {
+    member anticipatedConcurrentIncomingBidirectionalStreams // WebKit only as of 2025-12
+    member anticipatedConcurrentIncomingUnidirectionalStreams // WebKit only as of 2025-12
+    // No implementation as of 2025-12.
+    // WebKit has it in a different name datagramsReadableMode.
+    member datagramsReadableType
+  }
+}
diff --git a/inputfiles/removedTypes.jsonc b/inputfiles/removedTypes.jsonc
index df54f0c09..2ae5cb679 100644
--- a/inputfiles/removedTypes.jsonc
+++ b/inputfiles/removedTypes.jsonc
@@ -431,16 +431,6 @@
                     }
                 }
             },
-            "WebTransportOptions": {
-                "members": {
-                    "member": {
-                        "anticipatedConcurrentIncomingBidirectionalStreams": null, // No implementation as of 2025-07
-                        "anticipatedConcurrentIncomingUnidirectionalStreams": null, // No implementation as of 2025-07
-                        "datagramsReadableMode": null, // No implementation as of 2025-07
-                        "protocols": null // No implementation as of 2025-07
-                    }
-                }
-            },
             "WebTransportSendStreamOptions": {
                 "members": {
                     "member": {
diff --git a/package-lock.json b/package-lock.json
index 37e78a63f..7e08c6636 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -428,9 +428,9 @@
       }
     },
     "node_modules/@mdn/browser-compat-data": {
-      "version": "7.2.1",
-      "resolved": "https://registry.npmjs.org/@mdn/browser-compat-data/-/browser-compat-data-7.2.1.tgz",
-      "integrity": "sha512-t8gdzKeIHnPNACr18qlEpjLbbtazllkhwguEE3DSoGYL5OAKSqTacqNvXNLlXEjP1kTjT9Jkv3qNSMzNI4grPQ==",
+      "version": "7.2.2",
+      "resolved": "https://registry.npmjs.org/@mdn/browser-compat-data/-/browser-compat-data-7.2.2.tgz",
+      "integrity": "sha512-RoFRC9IzU4E0aSV1HXVz5kO7nSXjuSwEIprwSUlVuKKgk+s+wgO5tbe2iYNPqGLn1+w9HnqhqTVzrGpAPARLRQ==",
       "dev": true,
       "license": "CC0-1.0",
       "peer": true
@@ -1176,9 +1176,9 @@
       ]
     },
     "node_modules/@webref/css": {
-      "version": "8.1.1",
-      "resolved": "https://registry.npmjs.org/@webref/css/-/css-8.1.1.tgz",
-      "integrity": "sha512-YkLNPAdhR5BpO38ob82PsJx0xQMFtGGOVKmJQQu7jbBdxzcShcHd3t/Uo4oLxdZm0DV8gsyRK517r1Og99MkaA==",
+      "version": "8.1.2",
+      "resolved": "https://registry.npmjs.org/@webref/css/-/css-8.1.2.tgz",
+      "integrity": "sha512-AJqOQWZJZ00X5zRfUOFwaMwuUHOhmhf8FDuSOaZkTlBxcBj4Pq9jwlXUPxaORtR3Mcz6aMIFZ5ebKWvflkDQgw==",
       "dev": true,
       "license": "MIT",
       "peerDependencies": {
@@ -1200,9 +1200,9 @@
       "license": "MIT"
     },
     "node_modules/@webref/idl": {
-      "version": "3.70.0",
-      "resolved": "https://registry.npmjs.org/@webref/idl/-/idl-3.70.0.tgz",
-      "integrity": "sha512-6asVhcohvp3gmaYUl+NLfW9/7O9RS5aftvx/1CpXRDB45pdgEDRorh2yS/sZl+8UMmLXIu4xEF5KY6GUr8aOrQ==",
+      "version": "3.70.1",
+      "resolved": "https://registry.npmjs.org/@webref/idl/-/idl-3.70.1.tgz",
+      "integrity": "sha512-2yoAt9rRIg9vYLoX0y56IGkalWGQPvoi4b+bG36YHLehjYoHT9Naz22rO+4dWzK/tKfpi4hG5wTVFLjmojb5iQ==",
       "dev": true,
       "license": "MIT",
       "peer": true,