diff --git a/Source/WebKit/NetworkProcess/NetworkConnectionToWebProcess.cpp b/Source/WebKit/NetworkProcess/NetworkConnectionToWebProcess.cpp
index 24e9d0eecb573..105463225d611 100644
--- a/Source/WebKit/NetworkProcess/NetworkConnectionToWebProcess.cpp
+++ b/Source/WebKit/NetworkProcess/NetworkConnectionToWebProcess.cpp
@@ -75,6 +75,7 @@
 #include "WebsiteDataStoreParameters.h"
 #include <WebCore/DocumentStorageAccess.h>
 #include <WebCore/HTTPCookieAcceptPolicy.h>
+#include <WebCore/LegacySchemeRegistry.h>
 #include <WebCore/NetworkStorageSession.h>
 #include <WebCore/ResourceError.h>
 #include <WebCore/ResourceLoadObserver.h>
@@ -1441,6 +1442,11 @@ void NetworkConnectionToWebProcess::installMockContentFilter(WebCore::MockConten
 }
 #endif
 
+void NetworkConnectionToWebProcess::registerURLSchemeAsHandledBySchemeHandler(const String& scheme)
+{
+    WebCore::LegacySchemeRegistry::registerURLSchemeAsHandledBySchemeHandler(scheme);
+}
+
 } // namespace WebKit
 
 #undef CONNECTION_RELEASE_LOG
diff --git a/Source/WebKit/NetworkProcess/NetworkConnectionToWebProcess.h b/Source/WebKit/NetworkProcess/NetworkConnectionToWebProcess.h
index 35deb0171bee0..0828bb7f1fe1f 100644
--- a/Source/WebKit/NetworkProcess/NetworkConnectionToWebProcess.h
+++ b/Source/WebKit/NetworkProcess/NetworkConnectionToWebProcess.h
@@ -239,6 +239,8 @@ class NetworkConnectionToWebProcess
 
     void registerURLSchemesAsCORSEnabled(Vector<String>&& schemes);
 
+    void registerURLSchemeAsHandledBySchemeHandler(const String& scheme);
+
     void cookiesForDOM(const URL& firstParty, const WebCore::SameSiteInfo&, const URL&, WebCore::FrameIdentifier, WebCore::PageIdentifier, WebCore::IncludeSecureCookies, WebCore::ShouldAskITP, WebCore::ShouldRelaxThirdPartyCookieBlocking, CompletionHandler<void(String cookieString, bool secureCookiesAccessed)>&&);
     void setCookiesFromDOM(const URL& firstParty, const WebCore::SameSiteInfo&, const URL&, WebCore::FrameIdentifier, WebCore::PageIdentifier, WebCore::ShouldAskITP, const String&, WebCore::ShouldRelaxThirdPartyCookieBlocking);
     void cookieRequestHeaderFieldValue(const URL& firstParty, const WebCore::SameSiteInfo&, const URL&, std::optional<WebCore::FrameIdentifier>, std::optional<WebCore::PageIdentifier>, WebCore::IncludeSecureCookies, WebCore::ShouldAskITP, WebCore::ShouldRelaxThirdPartyCookieBlocking, CompletionHandler<void(String cookieString, bool secureCookiesAccessed)>&&);
diff --git a/Source/WebKit/NetworkProcess/NetworkConnectionToWebProcess.messages.in b/Source/WebKit/NetworkProcess/NetworkConnectionToWebProcess.messages.in
index 2ab3c78324601..4be02327c964f 100644
--- a/Source/WebKit/NetworkProcess/NetworkConnectionToWebProcess.messages.in
+++ b/Source/WebKit/NetworkProcess/NetworkConnectionToWebProcess.messages.in
@@ -117,4 +117,5 @@ messages -> NetworkConnectionToWebProcess LegacyReceiver {
 #if ENABLE(CONTENT_FILTERING_IN_NETWORKING_PROCESS)
     InstallMockContentFilter(WebCore::MockContentFilterSettings settings)
 #endif
+    RegisterURLSchemeAsHandledBySchemeHandler(String scheme)
 }
diff --git a/Source/WebKit/WebProcess/WebPage/WebPage.cpp b/Source/WebKit/WebProcess/WebPage/WebPage.cpp
index b8ec4d02e6713..540cd69c45a7a 100644
--- a/Source/WebKit/WebProcess/WebPage/WebPage.cpp
+++ b/Source/WebKit/WebProcess/WebPage/WebPage.cpp
@@ -7285,6 +7285,8 @@ void WebPage::registerURLSchemeHandler(WebURLSchemeHandlerIdentifier handlerIden
     WebCore::LegacySchemeRegistry::registerURLSchemeAsCORSEnabled(scheme);
     auto schemeResult = m_schemeToURLSchemeHandlerProxyMap.add(scheme, WebURLSchemeHandlerProxy::create(*this, handlerIdentifier));
     m_identifierToURLSchemeHandlerProxyMap.add(handlerIdentifier, schemeResult.iterator->value.get());
+
+    WebProcess::singleton().ensureNetworkProcessConnection().connection().send(Messages::NetworkConnectionToWebProcess::RegisterURLSchemeAsHandledBySchemeHandler { scheme }, 0);
 }
 
 void WebPage::urlSchemeTaskWillPerformRedirection(WebURLSchemeHandlerIdentifier handlerIdentifier, WebCore::ResourceLoaderIdentifier taskIdentifier, ResourceResponse&& response, ResourceRequest&& request, CompletionHandler<void(WebCore::ResourceRequest&&)>&& completionHandler)