diff --git a/src/plugins/qmldesigner/designmodewidget.cpp b/src/plugins/qmldesigner/designmodewidget.cpp
index d7e51dea4fb..7bd0faefa56 100644
--- a/src/plugins/qmldesigner/designmodewidget.cpp
+++ b/src/plugins/qmldesigner/designmodewidget.cpp
@@ -634,11 +634,12 @@ void DesignModeWidget::setup()
             openDocumentsWidget->setWindowTitle(tr("Open Documents"));
         }
 
-        if (navigationView.widget)
-            navigationView.widget->setStyleSheet(QLatin1String(
-                    Utils::FileReader::fetchQrc(":/qmldesigner/stylesheet.css")
-                    + Utils::FileReader::fetchQrc(":/qmldesigner/scrollbar.css")
-                    + "QLabel { background-color: #4f4f4f; }"));
+        if (navigationView.widget) {
+            QByteArray sheet = Utils::FileReader::fetchQrc(":/qmldesigner/stylesheet.css");
+            sheet += Utils::FileReader::fetchQrc(":/qmldesigner/scrollbar.css");
+            sheet += "QLabel { background-color: #4f4f4f; }";
+            navigationView.widget->setStyleSheet(QString::fromLatin1(sheet));
+        }
     }
 
     m_nodeInstanceView = new NodeInstanceView(this);
diff --git a/src/plugins/qmldesigner/styledoutputpaneplaceholder.cpp b/src/plugins/qmldesigner/styledoutputpaneplaceholder.cpp
index 44cd43a3ecf..24d73f315b8 100644
--- a/src/plugins/qmldesigner/styledoutputpaneplaceholder.cpp
+++ b/src/plugins/qmldesigner/styledoutputpaneplaceholder.cpp
@@ -42,9 +42,9 @@
 
 StyledOutputpanePlaceHolder::StyledOutputpanePlaceHolder(Core::IMode *mode, QSplitter *parent) : Core::OutputPanePlaceHolder(mode, parent)
 {
-    m_customStylesheet = QString::fromLatin1(
-            Utils::FileReader::fetchQrc(":/qmldesigner/outputpane-style.css")
-            + Utils::FileReader::fetchQrc(":/qmldesigner/scrollbar.css"));
+    QByteArray sheet = Utils::FileReader::fetchQrc(":/qmldesigner/outputpane-style.css");
+    sheet += Utils::FileReader::fetchQrc(":/qmldesigner/scrollbar.css");
+    m_customStylesheet = QString::fromLatin1(sheet);
 }
 
 void StyledOutputpanePlaceHolder::childEvent(QChildEvent *event)