diff --git a/webapp/src/main/scala/fmgp/webapp/SandboxSettings.scala b/webapp/src/main/scala/fmgp/webapp/SandboxSettings.scala
index ab2c4b8d..fa994c1f 100644
--- a/webapp/src/main/scala/fmgp/webapp/SandboxSettings.scala
+++ b/webapp/src/main/scala/fmgp/webapp/SandboxSettings.scala
@@ -15,7 +15,7 @@ object SandboxSettings {
         button(
           "Register URL protocol handler: web",
           onClick --> { _ =>
-            val n = dom.window.navigator.asInstanceOf[dom.NavigatorProtocolHandler]
+            val n = dom.window.navigator
             n.registerProtocolHandler("did", "#/resolver/%s")
             println("""registerProtocolHandler("did", "#/resolver/%s")""")
           },
@@ -23,7 +23,7 @@ object SandboxSettings {
         button(
           "Unregister URL protocol handler: web",
           onClick --> { _ =>
-            val n = dom.window.navigator.asInstanceOf[dom.NavigatorProtocolHandler]
+            val n = dom.window.navigator
             n.unregisterProtocolHandler("did", "#/resolver/%s")
             println("""unregisterProtocolHandler("did", "#/resolver/%s")""")
           },
@@ -41,7 +41,7 @@ object SandboxSettings {
         button(
           "Register URL protocol handler: web+did",
           onClick --> { _ =>
-            val n = dom.window.navigator.asInstanceOf[dom.NavigatorProtocolHandler]
+            val n = dom.window.navigator
             n.registerProtocolHandler("web+did", "#/resolver/%s")
             println("""registerProtocolHandler("web+did", "#/resolver/%s")""")
           },
@@ -49,7 +49,7 @@ object SandboxSettings {
         button(
           "Unregister URL protocol handler: web+did",
           onClick --> { _ =>
-            val n = dom.window.navigator.asInstanceOf[dom.NavigatorProtocolHandler]
+            val n = dom.window.navigator
             n.unregisterProtocolHandler("web+did", "#/resolver/%s")
             println("""unregisterProtocolHandler("web+did", "#/resolver/%s")""")
           },
diff --git a/webapp/src/main/scala/org/scalajs/dom/NavigatorProtocolHandler.scala b/webapp/src/main/scala/org/scalajs/dom/NavigatorProtocolHandler.scala
deleted file mode 100644
index edea6eb0..00000000
--- a/webapp/src/main/scala/org/scalajs/dom/NavigatorProtocolHandler.scala
+++ /dev/null
@@ -1,69 +0,0 @@
-package org.scalajs.dom
-
-import scala.scalajs.js
-
-@js.native
-trait NavigatorProtocolHandler extends js.Object {
-// trait NavigatorContentUtils extends js.Object {
-
-  /** The Navigator method registerProtocolHandler() lets websites register their ability to open or handle particular
-    * URL schemes (aka protocols).
-    *
-    * For example, this API lets webmail sites open mailto: URLs, or VoIP sites open tel: URLs.
-    *
-    * @see
-    *   https://developer.mozilla.org/en-US/docs/Web/API/Navigator/registerProtocolHandler
-    *
-    * @param scheme
-    *   A string containing the permitted scheme for the protocol that the site wishes to handle. For example, you can
-    *   register to handle SMS text message links by passing the "sms" scheme.
-    * @param url
-    *   A string containing the URL of the handler. This URL must include %s, as a placeholder that will be replaced
-    *   with the escaped URL to be handled.
-    * @return
-    *   undefined
-    *
-    * @throws DOMException.SECURITY_ERR
-    *   The user agent blocked the registration. This might happen if:
-    *   - The registered scheme (protocol) is invalid, such as a scheme the browser handles itself (https:, about:,
-    *     etc.)
-    *   - The handler URL's origin does not match the origin of the page calling this API.
-    *   - The browser requires that this function is called from a secure context.
-    *   - The browser requires that the handler's URL be over HTTPS.
-    *
-    * @throws DOMException.SYNTAX_ERR
-    *   The %s placeholder is missing from the handler URL
-    */
-  def registerProtocolHandler(scheme: String, url: String): Unit = js.native
-  def registerProtocolHandler(scheme: String, url: URL): Unit = js.native
-
-  /** The Navigator method unregisterProtocolHandler() removes a protocol handler for a given URL scheme.
-    *
-    * This method is the inverse of registerProtocolHandler().
-    *
-    * @see
-    *   https://developer.mozilla.org/en-US/docs/Web/API/Navigator/unregisterProtocolHandler
-    *
-    * @param scheme
-    *   A string containing the permitted scheme in the protocol handler that will be unregistered. For example, you can
-    *   unregister the handler for SMS text message links by passing the "sms" scheme.
-    * @param url
-    *   A string containing the URL of the handler. This URL should match the one that was used to register the handler
-    *   (e.g. it must include %s).
-    * @return
-    *   undefined
-    *
-    * @throws DOMException.SECURITY_ERR
-    *   The user agent blocked unregistration. This might happen if:
-    *   - The registered scheme (protocol) is invalid, such as a scheme the browser handles itself (https:, about:,
-    *     etc.)
-    *   - The handler URL's origin does not match the origin of the page calling this API.
-    *   - The browser requires that this function is called from a secure context.
-    *   - The browser requires that the handler's URL be over HTTPS.
-    *
-    * @throws DOMException.SYNTAX_ERR
-    *   The %s placeholder is missing from the handler URL
-    */
-  def unregisterProtocolHandler(scheme: String, url: String): Unit = js.native
-  def unregisterProtocolHandler(scheme: String, url: URL): Unit = js.native
-}