diff --git a/src/main.cpp b/src/main.cpp
index e37859b57..e5a19477b 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1,160 +1,175 @@
 /*
  * kmail: KDE mail client
  * Copyright (c) 1996-1998 Stefan Taferner <taferner@kde.org>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  *
  */
 
 #include <kontactinterface/pimuniqueapplication.h>
 
 #include "kmkernel.h" //control center
 #include "kmail_options.h"
 #include "kmmigrateapplication.h"
 
 #include "kmail_debug.h"
 #include <kmessagebox.h>
 #undef Status // stupid X headers
 
 #include "aboutdata.h"
 
 #include "kmstartup.h"
 
 #include <QDir>
 #include <QApplication>
 #include <QSessionManager>
 #include <KCrash>
 
 //-----------------------------------------------------------------------------
 
 class KMailApplication : public KontactInterface::PimUniqueApplication
 {
 public:
     KMailApplication(int &argc, char **argv[])
         : KontactInterface::PimUniqueApplication(argc, argv)
         , mDelayedInstanceCreation(false)
         , mEventLoopReached(false)
     {
     }
 
     int activate(const QStringList &args, const QString &workingDir) override;
     void commitData(QSessionManager &sm);
     void setEventLoopReached();
     void delayedInstanceCreation(const QStringList &args, const QString &workingDir);
+
+public Q_SLOTS:
+    int newInstance(const QByteArray &startupId, const QStringList &arguments, const QString &workingDirectory) override;
+
 protected:
     bool mDelayedInstanceCreation;
     bool mEventLoopReached;
 };
 
 void KMailApplication::commitData(QSessionManager &)
 {
     kmkernel->dumpDeadLetters();
     kmkernel->setShuttingDown(true);   // Prevent further dumpDeadLetters calls
 }
 
 void KMailApplication::setEventLoopReached()
 {
     mEventLoopReached = true;
 }
 
+int KMailApplication::newInstance(const QByteArray &startupId, const QStringList &arguments, const QString &workingDirectory)
+{
+    if (!kmkernel->firstInstance() && !arguments.isEmpty()) {
+        // if we're going to create a new window (viewer or composer),
+        // don't bring the mainwindow onto the current desktop
+        return activate(arguments, workingDirectory);
+    } else {
+        return PimUniqueApplication::newInstance(startupId, arguments, workingDirectory);
+    }
+}
+
 int KMailApplication::activate(const QStringList &args, const QString &workingDir)
 {
     // If the event loop hasn't been reached yet, the kernel is probably not
     // fully initialized. Creating an instance would therefore fail, this is why
     // that is delayed until delayedInstanceCreation() is called.
     if (!mEventLoopReached) {
         qCDebug(KMAIL_LOG) << "Delaying instance creation.";
         mDelayedInstanceCreation = true;
         return 0;
     }
 
     if (!kmkernel) {
         return 0;
     }
     if (kmkernel->shuttingDown()) {
         qCDebug(KMAIL_LOG) << "KMail is in a shutdown mode.";
         return 0;
     }
 
     if (!kmkernel->firstInstance() || !qApp->isSessionRestored()) {
         kmkernel->handleCommandLine(true, args, workingDir);
     }
     kmkernel->setFirstInstance(false);
     return 0;
 }
 
 void KMailApplication::delayedInstanceCreation(const QStringList &args, const QString &workingDir)
 {
     if (mDelayedInstanceCreation) {
         activate(args, workingDir);
     }
 }
 
 int main(int argc, char *argv[])
 {
 #if defined(Q_OS_UNIX) && QT_VERSION < QT_VERSION_CHECK(5, 11, 0)
     // enforce xcb plugin fix bug Bug 367598
     qputenv("QT_QPA_PLATFORM", "xcb");
 #endif
     QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
     KMailApplication app(argc, &argv);
     KLocalizedString::setApplicationDomain("kmail");
     app.setAttribute(Qt::AA_UseHighDpiPixmaps, true);
     app.setWindowIcon(QIcon::fromTheme(QStringLiteral("kmail")));
     app.setDesktopFileName(QStringLiteral("org.kde.kmail2"));
     KCrash::initialize();
     KMail::AboutData about;
     app.setAboutData(about);
 
     QCommandLineParser *cmdArgs = app.cmdArgs();
     kmail_options(cmdArgs);
 
     const QStringList args = QApplication::arguments();
     cmdArgs->process(args);
     about.processCommandLine(cmdArgs);
 
     if (!KMailApplication::start(args)) {
         qCDebug(KMAIL_LOG) << "Another instance of KMail already running";
         return 0;
     }
 
     KMMigrateApplication migrate;
     migrate.migrate();
 
     // import i18n data and icons from libraries:
     KMail::insertLibraryIcons();
 
     //local, do the init
     KMKernel kmailKernel;
     kmailKernel.init();
 
     // and session management
     kmailKernel.doSessionManagement();
 
     // any dead letters?
     kmailKernel.recoverDeadLetters();
 
     kmkernel->setupDBus(); // Ok. We are ready for D-Bus requests.
 
     //If the instance hasn't been created yet, do that now
     app.setEventLoopReached();
     app.delayedInstanceCreation(args, QDir::currentPath());
 
     // Go!
     int ret = qApp->exec();
     // clean up
     kmailKernel.cleanup();
     return ret;
 }