macOS: Disable auto window tabbing (#2261)

src/lib/app/mainapplication.cpp

@@ -243,6 +243,9 @@ MainApplication::MainApplication(int &argc, char** argv)
 
 #ifdef Q_OS_MACOS
     setQuitOnLastWindowClosed(false);
+    // disable tabbing issue#2261
+    extern void disableWindowTabbing();
+    disableWindowTabbing();
 #else
     setQuitOnLastWindowClosed(true);
 #endif

src/lib/lib.pro

@@ -485,6 +485,9 @@ mac {
     LIBS += -L$$BREW_OPENSSL/lib
 
     LIBS += -lcrypto -framework CoreServices
+
+    OBJECTIVE_SOURCES += tools/disablewindowtabbbing.mm
+    LIBS += -framework AppKit
 }
 
 message(===========================================)

src/lib/tools/disablewindowtabbbing.mm

@@ -0,0 +1,28 @@
+/* ============================================================
+* QupZilla - Qt web browser
+* Copyright (C) 2017 David Rosca <nowrep@gmail.com>
+* Copyright (C) 2017 S. Razi Alavizadeh <s.r.alavizadeh@gmail.com>
+*
+* 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 3 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, see <http://www.gnu.org/licenses/>.
+* ============================================================ */
+#import <AppKit/AppKit.h>
+
+// code taken from: https://www.mail-archive.com/interest@qt-project.org/msg23593.html
+// Disables auto window tabbing where supported, otherwise a no-op.
+void disableWindowTabbing()
+{
+    if ([NSWindow respondsToSelector:@selector(allowsAutomaticWindowTabbing)]) {
+        NSWindow.allowsAutomaticWindowTabbing = NO;
+    }
+}