No need to show a list for appstream://

If the user wants a different source, there's UI in the application page
to do so.
The delegates don't specify the source anyway.

discover/DiscoverObject.cpp

@@ -217,7 +217,30 @@ void DiscoverObject::openLocalPackage(const QUrl& localfile)
 void DiscoverObject::openApplication(const QUrl& url)
 {
     Q_ASSERT(!url.isEmpty());
-    Q_EMIT openUrl(url);
+    rootObject()->setProperty("defaultStartup", false);
+    auto action = new OneTimeAction(
+        [this, url]() {
+            AbstractResourcesBackend::Filters f;
+            f.resourceUrl = url;
+            auto stream = new StoredResultsStream({ResourcesModel::global()->search(f)});
+            connect(stream, &StoredResultsStream::finished, this, [this, url, stream]() {
+                const auto res = stream->resources();
+                qDebug() << "results..." << res;
+                if (res.count() == 1) {
+                    emit openApplicationInternal(res.first());
+                } else {
+                    rootObject()->setProperty("defaultStartup", true);
+                    showPassiveNotification(i18n("Couldn't open %1", url.toDisplayString()));
+                }
+            });
+        }
+        , this);
+
+    if (ResourcesModel::global()->backends().isEmpty()) {
+        connect(ResourcesModel::global(), &ResourcesModel::backendsChanged, action, &OneTimeAction::trigger);
+    } else {
+        action->trigger();
+    }
 }
 
 void DiscoverObject::integrateObject(QObject* object)

discover/DiscoverObject.h

@@ -76,7 +76,6 @@ class DiscoverObject : public QObject
     Q_SIGNALS:
         void openSearch(const QString &search);
         void openApplicationInternal(AbstractResource* app);
-        void openUrl(const QUrl& url);
         void listMimeInternal(const QString& mime);
         void listCategoryInternal(Category* cat);
 

discover/qml/DiscoverWindow.qml

@@ -97,10 +97,6 @@ Kirigami.ApplicationWindow
             Navigation.clearStack()
             Navigation.openApplication(app)
         }
-        onOpenUrl: {
-            currentTopLevel = topBrowsingComp;
-            Navigation.openUrlResources(url)
-        }
         onListMimeInternal:  {
             currentTopLevel = topBrowsingComp;
             Navigation.openApplicationMime(mime)

discover/qml/navigation.js

@@ -27,11 +27,6 @@ function openApplicationListSource(origin) {
     openApplicationList({ originFilter: origin, title: origin, allBackends: true })
 }
 
-function openUrlResources(uri) {
-    clearStack()
-    openApplicationList({ resourcesUrl: uri, title: uri, allBackends: true })
-}
-
 function openApplicationMime(mime) {
     clearStack()
     openApplicationList({ mimeTypeFilter: mime, title: i18n("Resources for '%1'", mime) })