How to apply this patch:

1. Import and apply it

2. cp browser/base/content/browser.xul browser/base/content/browser-kde.xul

3. Find editBookmarkPanelDoneButton

4. Replace #ifndef with #ifdef in the line above (this hanges the button order from Gnome-style to KDE-style)

5. hg qrefresh

       }, backoffTimes[this._backoffIndex]);

     }

+    var env = Components.classes["@mozilla.org/process/environment;1"]

+      .getService(Components.interfaces.nsIEnvironment);

+    var kde_session = 0;

+    if (env.get('KDE_FULL_SESSION') == "true") {

+      kde_session = 1;

+    }

+

     this.initBrowserContainers();

     this.buildContentProcessCountMenuList();

       }

       try {

         shellSvc.setDefaultBrowser(true, false);

+        if (kde_session == 1) {

+          var shellObj = Components.classes["@mozilla.org/file/local;1"]

+            .createInstance(Components.interfaces.nsILocalFile);

+          shellObj.initWithPath("/usr/bin/kwriteconfig");

+          var process = Components.classes["@mozilla.org/process/util;1"]

+            .createInstance(Components.interfaces.nsIProcess);

+          process.init(shellObj);

+          var args = ["--file", "kdeglobals", "--group", "General", "--key",

+              "BrowserApplication", "firefox"];

+          process.run(false, args, args.length);

+        }

       } catch (ex) {

         console.error(ex);

         return;

     SOURCES += [

         "nsGNOMEShellService.cpp",

+        "nsKDEShellService.cpp",

+        "nsUnixShellService.cpp",

     ]

     if CONFIG["MOZ_ENABLE_DBUS"]:

         SOURCES += [

--- /dev/null

@@ -0,0 +1,109 @@

+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

+/* This Source Code Form is subject to the terms of the Mozilla Public

+ * License, v. 2.0. If a copy of the MPL was not distributed with this

+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

+

+#include "mozilla/ArrayUtils.h"

+

+#include "nsCOMPtr.h"

+#include "nsKDEShellService.h"

+#include "nsShellService.h"

+#include "nsKDEUtils.h"

+#include "nsIPrefService.h"

+#include "nsIProcess.h"

+#include "nsIFile.h"

+#include "nsServiceManagerUtils.h"

+#include "nsComponentManagerUtils.h"

+#include "nsIMutableArray.h"

+#include "nsISupportsPrimitives.h"

+#include "nsArrayUtils.h"

+

+using namespace mozilla;

+

+nsresult

+nsKDEShellService::Init()

+{

+    if( !nsKDEUtils::kdeSupport())

+        return NS_ERROR_NOT_AVAILABLE;

+    return NS_OK;

+}

+

+NS_IMPL_ISUPPORTS(nsKDEShellService, nsIGNOMEShellService, nsIShellService)

+

+NS_IMETHODIMP

+nsKDEShellService::IsDefaultBrowser(bool aForAllTypes,

+                                    bool* aIsDefaultBrowser)

+{

+    *aIsDefaultBrowser = false;

+

+    nsCOMPtr<nsIMutableArray> command = do_CreateInstance( NS_ARRAY_CONTRACTID );

+    if (!command)

+        return NS_ERROR_FAILURE;

+

+    nsCOMPtr<nsISupportsCString> str = do_CreateInstance( NS_SUPPORTS_CSTRING_CONTRACTID );

+    if (!str)

+        return NS_ERROR_FAILURE;

+

+    str->SetData("ISDEFAULTBROWSER"_ns);

+    command->AppendElement( str );

+

+    if( nsKDEUtils::command( command ))

+        *aIsDefaultBrowser = true;

+    return NS_OK;

+}

+

+NS_IMETHODIMP

+nsKDEShellService::SetDefaultBrowser(bool aClaimAllTypes,

+                                     bool aForAllUsers)

+{

+    nsCOMPtr<nsIMutableArray> command = do_CreateInstance( NS_ARRAY_CONTRACTID );

+    if (!command)

+        return NS_ERROR_FAILURE;

+

+    nsCOMPtr<nsISupportsCString> cmdstr = do_CreateInstance( NS_SUPPORTS_CSTRING_CONTRACTID );

+    nsCOMPtr<nsISupportsCString> paramstr = do_CreateInstance( NS_SUPPORTS_CSTRING_CONTRACTID );

+    if (!cmdstr || !paramstr)

+        return NS_ERROR_FAILURE;

+

+    cmdstr->SetData("SETDEFAULTBROWSER"_ns);

+    command->AppendElement( cmdstr );

+

+    paramstr->SetData( aClaimAllTypes ? "ALLTYPES"_ns : "NORMAL"_ns );

+    command->AppendElement( paramstr );

+

+    return nsKDEUtils::command( command ) ? NS_OK : NS_ERROR_FAILURE;

+}

+

+NS_IMETHODIMP

+nsKDEShellService::GetCanSetDesktopBackground(bool* aResult)

+{

+  *aResult = true;

+  return NS_OK;

+}

+

+NS_IMETHODIMP

+nsKDEShellService::SetDesktopBackground(dom::Element* aElement,

+                                        int32_t aPosition,

+                                        const nsACString& aImageName)

+{

+    return NS_ERROR_NOT_IMPLEMENTED;

+}

+

+NS_IMETHODIMP

+nsKDEShellService::GetDesktopBackgroundColor(PRUint32 *aColor)

+{

+    return NS_ERROR_NOT_IMPLEMENTED;

+}

+

+NS_IMETHODIMP

+nsKDEShellService::SetDesktopBackgroundColor(PRUint32 aColor)

+{

+    return NS_ERROR_NOT_IMPLEMENTED;

+}

+

+NS_IMETHODIMP

+nsKDEShellService::IsDefaultForScheme(nsTSubstring<char> const& aScheme, bool* aIsDefaultBrowser)

+{

+    return NS_ERROR_NOT_IMPLEMENTED;

+}

+

--- /dev/null

@@ -0,0 +1,32 @@

+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

+/* This Source Code Form is subject to the terms of the Mozilla Public

+ * License, v. 2.0. If a copy of the MPL was not distributed with this

+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

+

+#ifndef nskdeshellservice_h____

+#define nskdeshellservice_h____

+

+#include "nsIGNOMEShellService.h"

+#include "nsToolkitShellService.h"

+#include "nsString.h"

+#include "mozilla/Attributes.h"

+

+class nsKDEShellService final : public nsIGNOMEShellService,

+                                public nsToolkitShellService

+{

+public:

+  nsKDEShellService() : mCheckedThisSession(false) { }

+

+  NS_DECL_ISUPPORTS

+  NS_DECL_NSISHELLSERVICE

+  NS_DECL_NSIGNOMESHELLSERVICE

+

+  nsresult Init();

+

+private:

+  ~nsKDEShellService() {}

+

+  bool mCheckedThisSession;

+};

+

+#endif // nskdeshellservice_h____

--- /dev/null

@@ -0,0 +1,22 @@

+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

+/* This Source Code Form is subject to the terms of the Mozilla Public

+ * License, v. 2.0. If a copy of the MPL was not distributed with this

+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

+

+

+#include "nsUnixShellService.h"

+#include "nsGNOMEShellService.h"

+#include "nsKDEShellService.h"

+#include "nsKDEUtils.h"

+#include "mozilla/ModuleUtils.h"

+

+NS_GENERIC_FACTORY_CONSTRUCTOR_INIT(nsGNOMEShellService, Init)

+NS_GENERIC_FACTORY_CONSTRUCTOR_INIT(nsKDEShellService, Init)

+

+NS_IMETHODIMP

+nsUnixShellServiceConstructor(REFNSIID aIID, void **aResult)

+{

+    if( nsKDEUtils::kdeSupport())

+        return nsKDEShellServiceConstructor( aIID, aResult );

+    return nsGNOMEShellServiceConstructor( aIID, aResult );

+}

--- /dev/null

@@ -0,0 +1,15 @@

+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

+/* This Source Code Form is subject to the terms of the Mozilla Public

+ * License, v. 2.0. If a copy of the MPL was not distributed with this

+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

+

+

+#ifndef nsunixshellservice_h____

+#define nsunixshellservice_h____

+

+#include "nsIGNOMEShellService.h"

+

+NS_IMETHODIMP

+nsUnixShellServiceConstructor(nsISupports *aOuter, REFNSIID aIID, void **aResult);

+

+#endif // nsunixshellservice_h____