--- a/mobile/android/base/java/org/mozilla/gecko/IntentHelper.java
+++ b/mobile/android/base/java/org/mozilla/gecko/IntentHelper.java
@@ -58,19 +58,16 @@ public final class IntentHelper implemen
         "Intent:OpenForResult",
         "Intent:OpenNoHandler",
     };
 
     // via http://developer.android.com/distribute/tools/promote/linking.html
     private static final String MARKET_INTENT_URI_PACKAGE_PREFIX = "market://details?id=";
     private static final String EXTRA_BROWSER_FALLBACK_URL = "browser_fallback_url";
 
-    /** A partial URI to an error page - the encoded error URI should be appended before loading. */
-    private static final String UNKNOWN_PROTOCOL_URI_PREFIX = "about:neterror?e=unknownProtocolFound&u=";
-
     private static IntentHelper instance;
 
     private IntentHelper() {
         EventDispatcher.getInstance().registerGeckoThreadListener(this, GECKO_EVENTS);
         EventDispatcher.getInstance().registerUiThreadListener(this, UI_EVENTS);
     }
 
     public static IntentHelper init() {
@@ -500,37 +497,28 @@ public final class IntentHelper implemen
      *                 the uri to load if Java does not load a page
      */
     private void openNoHandler(final GeckoBundle msg, final EventCallback callback) {
         final String uri = msg.getString("uri");
         final GeckoBundle errorResponse = new GeckoBundle();
 
         if (TextUtils.isEmpty(uri)) {
             Log.w(LOGTAG, "Received empty URL - loading about:neterror");
-            errorResponse.putString("uri", getUnknownProtocolErrorPageUri(""));
             errorResponse.putBoolean("isFallback", false);
             callback.sendError(errorResponse);
             return;
         }
 
         final Intent intent;
         try {
             // TODO (bug 1173626): This will not handle android-app uris on non 5.1 devices.
             intent = Intent.parseUri(uri, 0);
         } catch (final URISyntaxException e) {
-            String errorUri;
-            try {
-                errorUri = getUnknownProtocolErrorPageUri(URLEncoder.encode(uri, "UTF-8"));
-            } catch (final UnsupportedEncodingException encodingE) {
-                errorUri = getUnknownProtocolErrorPageUri("");
-            }
-
             // Don't log the exception to prevent leaking URIs.
             Log.w(LOGTAG, "Unable to parse Intent URI - loading about:neterror");
-            errorResponse.putString("uri", errorUri);
             errorResponse.putBoolean("isFallback", false);
             callback.sendError(errorResponse);
             return;
         }
 
         // For this flow, we follow Chrome's lead:
         //   https://developer.chrome.com/multidevice/android/intents
         final String fallbackUrl = intent.getStringExtra(EXTRA_BROWSER_FALLBACK_URL);
@@ -570,17 +558,16 @@ public final class IntentHelper implemen
             // many websites have catered to this behavior. For example, the site might set a timeout and load a play
             // store url for their app if the intent link fails to load, i.e. the app is not installed.
             // These work-arounds would often end with our users seeing about:neterror instead of the intended experience.
             // While I feel showing about:neterror is a better solution for users (when not hacked around),
             // we should match the status quo for the good of our users.
             //
             // Don't log the URI to prevent leaking it.
             Log.w(LOGTAG, "Unable to open URI, maybe showing neterror");
-            errorResponse.putString("uri", getUnknownProtocolErrorPageUri(intent.getData().toString()));
             errorResponse.putBoolean("isFallback", false);
             callback.sendError(errorResponse);
         }
     }
 
     private static boolean isFallbackUrlValid(@Nullable final String fallbackUrl) {
         if (fallbackUrl == null) {
             return false;
@@ -596,26 +583,16 @@ public final class IntentHelper implemen
             }
         } catch (final URISyntaxException e) {
             // Do not include Exception to avoid leaking uris.
             Log.w(LOGTAG, "URISyntaxException parsing fallback URI");
         }
         return false;
     }
 
-    /**
-     * Returns an about:neterror uri with the unknownProtocolFound text as a parameter.
-     * @param encodedUri The encoded uri. While the page does not open correctly without specifying
-     *                   a uri parameter, it happily accepts the empty String so this argument may
-     *                   be the empty String.
-     */
-    private String getUnknownProtocolErrorPageUri(final String encodedUri) {
-        return UNKNOWN_PROTOCOL_URI_PREFIX + encodedUri;
-    }
-
     private static class ResultHandler implements ActivityResultHandler {
         private final EventCallback callback;
 
         public ResultHandler(final EventCallback callback) {
             this.callback = callback;
         }
 
         @Override

--- a/mobile/android/chrome/content/browser.js
+++ b/mobile/android/chrome/content/browser.js
@@ -4563,17 +4563,18 @@ Tab.prototype = {
     }
 
     // Update the page actions URI for helper apps.
     if (BrowserApp.selectedTab == this) {
       ExternalApps.updatePageActionUri(fixedURI);
     }
 
     if ((!aRequest || Components.isSuccessCode(aRequest.status)) &&
-        !fixedURI.displaySpec.startsWith("about:neterror") && !this.isSearch) {
+        !(aFlags & Ci.nsIWebProgressListener.LOCATION_CHANGE_ERROR_PAGE) &&
+        !this.isSearch) {
       // If this won't end up in an error page and the user isn't searching,
       // don't retain the typed entry.
       this.userRequested = "";
     }
 
     let message = {
       type: "Content:LocationChange",
       tabID: this.id,

--- a/mobile/android/components/ContentDispatchChooser.js
+++ b/mobile/android/components/ContentDispatchChooser.js
@@ -81,17 +81,17 @@ ContentDispatchChooser.prototype =
         }
 
         // We couldn't open this. If this was from a click, it's likely that we just
         // want this to fail silently. If the user entered this on the address bar, though,
         // we want to show the neterror page.
         let dwu = window.QueryInterface(Ci.nsIInterfaceRequestor).getInterface(Ci.nsIDOMWindowUtils);
         let millis = dwu.millisSinceLastUserInput;
         if (millis < 0 || millis >= 1000) {
-          window.location.href = data.uri;
+          window.document.docShell.displayLoadError(Cr.NS_ERROR_UNKNOWN_PROTOCOL, aURI, null);
         } else {
           this._closeBlankWindow(window);
         }
       });
     }
   },
 };