diff --git a/mobile/shared/actors/ContentDelegateChild.sys.mjs b/mobile/shared/actors/ContentDelegateChild.sys.mjs
index 5269fe3fd9b..f5a30687b2c 100644
--- a/mobile/shared/actors/ContentDelegateChild.sys.mjs
+++ b/mobile/shared/actors/ContentDelegateChild.sys.mjs
@@ -27,10 +27,7 @@ export class ContentDelegateChild extends GeckoViewActorChild {
           return;
         }
         this.lastViewportFit = viewportFit;
-        this.eventDispatcher.sendRequest({
-          type: "GeckoView:DOMMetaViewportFit",
-          viewportfit: viewportFit,
-        });
+        this.sendAsyncMessage("GeckoView:DOMMetaViewportFit", viewportFit);
       }
     );
   }
@@ -179,7 +176,6 @@ export class ContentDelegateChild extends GeckoViewActorChild {
 
         if (uri || isImage || isMedia) {
           const msg = {
-            type: "GeckoView:ContextMenu",
             // We don't have full zoom on Android, so using CSS coordinates
             // here is fine, since the CSS coordinate spaces match between the
             // child and parent processes.
@@ -200,13 +196,13 @@ export class ContentDelegateChild extends GeckoViewActorChild {
               null,
           };
 
-          this.eventDispatcher.sendRequest(msg);
+          this.sendAsyncMessage("GeckoView:ContextMenu", msg);
           aEvent.preventDefault();
         }
         break;
       }
       case "MozDOMFullscreen:Request": {
-        this.sendAsyncMessage("GeckoView:DOMFullscreenRequest", {});
+        this.sendAsyncMessage("GeckoView:DOMFullscreenRequest");
         break;
       }
       case "MozDOMFullscreen:Entered":
@@ -219,7 +215,7 @@ export class ContentDelegateChild extends GeckoViewActorChild {
         }
       // fall-through
       case "MozDOMFullscreen:Exit":
-        this.sendAsyncMessage("GeckoView:DOMFullscreenExit", {});
+        this.sendAsyncMessage("GeckoView:DOMFullscreenExit");
         break;
       case "DOMMetaViewportFitChanged":
         if (aEvent.originalTarget.ownerGlobal == this.contentWindow) {
@@ -241,24 +237,17 @@ export class ContentDelegateChild extends GeckoViewActorChild {
             this.contentWindow
           );
           if (manifest) {
-            this.eventDispatcher.sendRequest({
-              type: "GeckoView:WebAppManifest",
-              manifest,
-            });
+            this.sendAsyncMessage("GeckoView:WebAppManifest", manifest);
           }
         });
         break;
       }
       case "MozFirstContentfulPaint": {
-        this.eventDispatcher.sendRequest({
-          type: "GeckoView:FirstContentfulPaint",
-        });
+        this.sendAsyncMessage("GeckoView:FirstContentfulPaint");
         break;
       }
       case "MozPaintStatusReset": {
-        this.eventDispatcher.sendRequest({
-          type: "GeckoView:PaintStatusReset",
-        });
+        this.sendAsyncMessage("GeckoView:PaintStatusReset");
         break;
       }
     }
diff --git a/mobile/shared/actors/ContentDelegateParent.sys.mjs b/mobile/shared/actors/ContentDelegateParent.sys.mjs
index d621c801047..f11fde38f52 100644
--- a/mobile/shared/actors/ContentDelegateParent.sys.mjs
+++ b/mobile/shared/actors/ContentDelegateParent.sys.mjs
@@ -29,6 +29,39 @@ export class ContentDelegateParent extends GeckoViewActorParent {
         this.window.windowUtils.remoteFrameFullscreenChanged(this.browser);
         return null;
       }
+
+      case "GeckoView:DOMMetaViewportFit": {
+        return this.eventDispatcher.sendRequest({
+          viewportfit: aMsg.data,
+          type: "GeckoView:DOMMetaViewportFit",
+        });
+      }
+
+      case "GeckoView:ContextMenu": {
+        return this.eventDispatcher.sendRequest({
+          ...aMsg.data,
+          type: "GeckoView:ContextMenu",
+        });
+      }
+
+      case "GeckoView:WebAppManifest": {
+        return this.eventDispatcher.sendRequest({
+          manifest: aMsg.data,
+          type: "GeckoView:WebAppManifest",
+        });
+      }
+
+      case "GeckoView:FirstContentfulPaint": {
+        return this.eventDispatcher.sendRequest({
+          type: "GeckoView:FirstContentfulPaint",
+        });
+      }
+
+      case "GeckoView:PaintStatusReset": {
+        return this.eventDispatcher.sendRequest({
+          type: "GeckoView:PaintStatusReset",
+        });
+      }
     }
 
     return super.receiveMessage(aMsg);
diff --git a/mobile/shared/actors/GeckoViewContentChild.sys.mjs b/mobile/shared/actors/GeckoViewContentChild.sys.mjs
index 23cfc73de50..cef3910b568 100644
--- a/mobile/shared/actors/GeckoViewContentChild.sys.mjs
+++ b/mobile/shared/actors/GeckoViewContentChild.sys.mjs
@@ -32,8 +32,6 @@ export class GeckoViewContentChild extends GeckoViewActorChild {
   }
 
   actorCreated() {
-    super.actorCreated();
-
     this.pageShow = new Promise(resolve => {
       this.receivedPageShow = resolve;
     });
@@ -335,8 +333,7 @@ export class GeckoViewContentChild extends GeckoViewActorChild {
           aEvent.reason === "presscaret" ||
           aEvent.reason === "releasecaret"
         ) {
-          this.eventDispatcher.sendRequest({
-            type: "GeckoView:PinOnScreen",
+          this.sendAsyncMessage("GeckoView:PinOnScreen", {
             pinned: aEvent.reason === "presscaret",
           });
         }
diff --git a/mobile/shared/actors/GeckoViewContentParent.sys.mjs b/mobile/shared/actors/GeckoViewContentParent.sys.mjs
index 069894ba967..8f61cfaf64c 100644
--- a/mobile/shared/actors/GeckoViewContentParent.sys.mjs
+++ b/mobile/shared/actors/GeckoViewContentParent.sys.mjs
@@ -28,6 +28,20 @@ export class GeckoViewContentParent extends GeckoViewActorParent {
     return this.sendQuery("ContainsFormData");
   }
 
+  async receiveMessage(aMsg) {
+    switch (aMsg.name) {
+      case "GeckoView:PinOnScreen": {
+        return this.eventDispatcher.sendRequest({
+          ...aMsg.data,
+          type: "GeckoView:PinOnScreen",
+        });
+      }
+      default: {
+        return super.receiveMessage(aMsg);
+      }
+    }
+  }
+
   restoreState({ history, switchId, formdata, scrolldata }) {
     if (Services.appinfo.sessionHistoryInParent) {
       const { browsingContext } = this.browser;
diff --git a/mobile/shared/actors/GeckoViewPermissionChild.sys.mjs b/mobile/shared/actors/GeckoViewPermissionChild.sys.mjs
index bbe9457cc5e..d454250bb56 100644
--- a/mobile/shared/actors/GeckoViewPermissionChild.sys.mjs
+++ b/mobile/shared/actors/GeckoViewPermissionChild.sys.mjs
@@ -20,8 +20,7 @@ const MAPPED_TO_EXTENSION_PERMISSIONS = [
 
 export class GeckoViewPermissionChild extends GeckoViewActorChild {
   getMediaPermission(aPermission) {
-    return this.eventDispatcher.sendRequestForResult({
-      type: "GeckoView:MediaPermission",
+    return this.sendQuery("GeckoView:MediaPermission", {
       ...aPermission,
     });
   }
@@ -35,8 +34,7 @@ export class GeckoViewPermissionChild extends GeckoViewActorChild {
   }
 
   mediaRecordingStatusChanged(aDevices) {
-    return this.eventDispatcher.sendRequest({
-      type: "GeckoView:MediaRecordingStatusChanged",
+    return this.sendAsyncMessage("GeckoView:MediaRecordingStatusChanged", {
       devices: aDevices,
     });
   }
@@ -132,8 +130,7 @@ export class GeckoViewPermissionChild extends GeckoViewActorChild {
 
     let allowOrDeny;
     try {
-      allowOrDeny = await this.eventDispatcher.sendRequestForResult({
-        type: "GeckoView:ContentPermission",
+      allowOrDeny = await this.sendQuery("GeckoView:ContentPermission", {
         uri: principal.URI.displaySpec,
         thirdPartyOrigin: aRequest.principal.origin,
         principal: lazy.E10SUtils.serializePrincipal(principal),
diff --git a/mobile/shared/actors/GeckoViewPermissionParent.sys.mjs b/mobile/shared/actors/GeckoViewPermissionParent.sys.mjs
index c4a5cf56cf0..867fc31bdbd 100644
--- a/mobile/shared/actors/GeckoViewPermissionParent.sys.mjs
+++ b/mobile/shared/actors/GeckoViewPermissionParent.sys.mjs
@@ -56,6 +56,24 @@ export class GeckoViewPermissionParent extends GeckoViewActorParent {
       case "AddCameraPermission": {
         return this.addCameraPermission();
       }
+      case "GeckoView:MediaPermission": {
+        return this.eventDispatcher.sendRequestForResult({
+          ...aMessage.data,
+          type: "GeckoView:MediaPermission",
+        });
+      }
+      case "GeckoView:MediaRecordingStatusChanged": {
+        return this.eventDispatcher.sendRequest({
+          ...aMessage.data,
+          type: "GeckoView:MediaRecordingStatusChanged",
+        });
+      }
+      case "GeckoView:ContentPermission": {
+        return this.eventDispatcher.sendRequestForResult({
+          ...aMessage.data,
+          type: "GeckoView:ContentPermission",
+        });
+      }
     }
 
     return super.receiveMessage(aMessage);
diff --git a/mobile/shared/actors/GeckoViewPrompterChild.sys.mjs b/mobile/shared/actors/GeckoViewPrompterChild.sys.mjs
index bb8c4fbcff5..dd84f554cc1 100644
--- a/mobile/shared/actors/GeckoViewPrompterChild.sys.mjs
+++ b/mobile/shared/actors/GeckoViewPrompterChild.sys.mjs
@@ -11,16 +11,14 @@ export class GeckoViewPrompterChild extends GeckoViewActorChild {
   }
 
   dismissPrompt(prompt) {
-    this.eventDispatcher.sendRequest({
-      type: "GeckoView:Prompt:Dismiss",
+    this.sendAsyncMessage("GeckoView:Prompt:Dismiss", {
       id: prompt.id,
     });
     this.unregisterPrompt(prompt);
   }
 
   updatePrompt(message) {
-    this.eventDispatcher.sendRequest({
-      type: "GeckoView:Prompt:Update",
+    this.sendAsyncMessage("GeckoView:Prompt:Update", {
       prompt: message,
     });
   }
@@ -41,8 +39,7 @@ export class GeckoViewPrompterChild extends GeckoViewActorChild {
     // We intentionally do not await here as we want to fire NotifyPromptShow
     // immediately rather than waiting until the user accepts/dismisses the
     // prompt.
-    const result = this.eventDispatcher.sendRequestForResult({
-      type: "GeckoView:Prompt",
+    const result = this.sendQuery("GeckoView:Prompt", {
       prompt: message,
     });
     this.sendAsyncMessage("NotifyPromptShow", {
diff --git a/mobile/shared/actors/GeckoViewPrompterParent.sys.mjs b/mobile/shared/actors/GeckoViewPrompterParent.sys.mjs
index 24b763b114b..6f4d0f76f11 100644
--- a/mobile/shared/actors/GeckoViewPrompterParent.sys.mjs
+++ b/mobile/shared/actors/GeckoViewPrompterParent.sys.mjs
@@ -122,6 +122,26 @@ export class GeckoViewPrompterParent extends GeckoViewActorParent {
         this.rootActor.notifyPromptShow(data.id);
         break;
       }
+      case "GeckoView:Prompt:Dismiss": {
+        return this.eventDispatcher.sendRequest({
+          ...data,
+          type: "GeckoView:Prompt:Dismiss",
+        });
+        break;
+      }
+      case "GeckoView:Prompt:Update": {
+        this.eventDispatcher.sendRequest({
+          ...data,
+          type: "GeckoView:Prompt:Update",
+        });
+        break;
+      }
+      case "GeckoView:Prompt": {
+        return this.eventDispatcher.sendRequestForResult({
+          ...data,
+          type: "GeckoView:Prompt",
+        });
+      }
       default: {
         return super.receiveMessage({ name, data });
       }
diff --git a/mobile/shared/actors/LoadURIDelegateChild.sys.mjs b/mobile/shared/actors/LoadURIDelegateChild.sys.mjs
index 80ab0db0bc1..8a22300f297 100644
--- a/mobile/shared/actors/LoadURIDelegateChild.sys.mjs
+++ b/mobile/shared/actors/LoadURIDelegateChild.sys.mjs
@@ -17,13 +17,26 @@ export class LoadURIDelegateChild extends GeckoViewActorChild {
     debug`handleLoadError: uri=${aUri && aUri.spec}
                              displaySpec=${aUri && aUri.displaySpec}
                              error=${aError}`;
+    let errorClass = 0;
+    try {
+      const nssErrorsService = Cc[
+        "@mozilla.org/nss_errors_service;1"
+      ].getService(Ci.nsINSSErrorsService);
+      errorClass = nssErrorsService.getErrorClass(aError);
+    } catch (e) {}
+
+    const msg = {
+      uri: aUri && aUri.spec,
+      error: aError,
+      errorModule: aErrorModule,
+      errorClass,
+    };
+
+    let errorPagePromise = this.sendQuery("GeckoView:OnLoadError", msg);
 
     return lazy.LoadURIDelegate.handleLoadError(
       this.contentWindow,
-      this.eventDispatcher,
-      aUri,
-      aError,
-      aErrorModule
+      errorPagePromise
     );
   }
 }
diff --git a/mobile/shared/actors/LoadURIDelegateParent.sys.mjs b/mobile/shared/actors/LoadURIDelegateParent.sys.mjs
index 0446d7d88a4..ead98dc1130 100644
--- a/mobile/shared/actors/LoadURIDelegateParent.sys.mjs
+++ b/mobile/shared/actors/LoadURIDelegateParent.sys.mjs
@@ -4,5 +4,18 @@
 
 import { GeckoViewActorParent } from "resource://gre/modules/GeckoViewActorParent.sys.mjs";
 
-// For this.eventDispatcher in the child
-export class LoadURIDelegateParent extends GeckoViewActorParent {}
+export class LoadURIDelegateParent extends GeckoViewActorParent {
+  async receiveMessage({ name, data }) {
+    switch (name) {
+      case "GeckoView:OnLoadError": {
+        return this.eventDispatcher.sendRequestForResult({
+          ...data,
+          type: "GeckoView:OnLoadError",
+        });
+      }
+      default: {
+        return super.receiveMessage({ name, data });
+      }
+    }
+  }
+}
diff --git a/mobile/shared/actors/MediaControlDelegateChild.sys.mjs b/mobile/shared/actors/MediaControlDelegateChild.sys.mjs
index 1db32b33f05..0fa1daabd47 100644
--- a/mobile/shared/actors/MediaControlDelegateChild.sys.mjs
+++ b/mobile/shared/actors/MediaControlDelegateChild.sys.mjs
@@ -34,11 +34,13 @@ export class MediaControlDelegateChild extends GeckoViewActorChild {
       debug`No fullscreen media element found.`;
     }
 
-    const activated = await this.eventDispatcher.sendRequestForResult({
-      type: "GeckoView:MediaSession:Fullscreen",
-      metadata: lazy.MediaUtils.getMetadata(mediaElement) ?? {},
-      enabled: !!element,
-    });
+    const activated = await this.sendQuery(
+      "GeckoView:MediaSession:Fullscreen",
+      {
+        metadata: lazy.MediaUtils.getMetadata(mediaElement) ?? {},
+        enabled: !!element,
+      }
+    );
     if (activated) {
       return;
     }
diff --git a/mobile/shared/actors/MediaControlDelegateParent.sys.mjs b/mobile/shared/actors/MediaControlDelegateParent.sys.mjs
index f0c3f479846..ad19dcf9f23 100644
--- a/mobile/shared/actors/MediaControlDelegateParent.sys.mjs
+++ b/mobile/shared/actors/MediaControlDelegateParent.sys.mjs
@@ -4,5 +4,18 @@
 
 import { GeckoViewActorParent } from "resource://gre/modules/GeckoViewActorParent.sys.mjs";
 
-// For this.eventDispatcher in the child
-export class MediaControlDelegateParent extends GeckoViewActorParent {}
+export class MediaControlDelegateParent extends GeckoViewActorParent {
+  async receiveMessage({ name, data }) {
+    switch (name) {
+      case "GeckoView:MediaSession:Fullscreen": {
+        return this.eventDispatcher.sendRequestForResult({
+          ...data,
+          type: "GeckoView:MediaSession:Fullscreen",
+        });
+      }
+      default: {
+        return super.receiveMessage({ name, data });
... (file diff truncated)