From: <kabe@>
Subject: Allow null URL "" to be opened via kfmclient

When Konqueror is launched via App Launcher->Favorites,
it could be passed a null URL (kfmclient openURL "" text/html),
which bombs out othewise as

	The requested operation could not be completed
	Details ot the request:
	URL:				<<< blank

Try open the "home page" if passed a blank URL.


diff -up ./client/konqclientrequest.cpp.00 ./client/konqclientrequest.cpp
--- ./client/konqclientrequest.cpp.00	2020-01-13 17:35:10.000000000 +0900
+++ ./client/konqclientrequest.cpp	2021-09-06 22:17:34.597407883 +0900
@@ -122,7 +122,10 @@ bool KonqClientRequest::openUrl()
         }
     }
 
-    QDBusReply<QDBusObjectPath> reply = konq.createNewWindow(d->url.toString(), d->mimeType, d->startup_id_str, d->tempFile);
+    // Pass some URL meaningful if Konqueror is already running.
+    // We want to let it open the default homepage, but no way to
+    // specify it explicitly.
+    QDBusReply<QDBusObjectPath> reply = konq.createNewWindow(d->url.isEmpty()?"about:":d->url.toString(), d->mimeType, d->startup_id_str, d->tempFile);
     if (reply.isValid()) {
         d->sendASNChange();
         return true;
@@ -139,7 +142,11 @@ bool KonqClientRequest::openUrl()
         if (d->tempFile) {
             args << QStringLiteral("-tempfile");
         }
-        args << d->url.toEncoded();
+        if (!d->url.isEmpty()) {
+            // Only add URL argument if it is not "".
+            // KDE App Launcher->Favorites->Konqueror could pass a null string.
+            args << d->url.toEncoded();
+        }
         qint64 pid;
 #ifdef Q_OS_WIN
         const bool ok = QProcess::startDetached(QStringLiteral("kwrapper5"), args, QString(), &pid);