Only check color theme on first run, not each time the Wizard is called

BUG:388274

src/dialogs/wizard.cpp

@@ -74,8 +74,6 @@ Wizard::Wizard(bool autoClose, QWidget *parent) :
     m_systemCheckIsOk(false),
     m_brokenModule(false)
 {
-    // Check color theme
-    ThemeManager::instance()->initDarkTheme();
     setWindowTitle(i18n("Welcome to Kdenlive"));
     int logoHeight = fontMetrics().height() * 2.5;
     setWizardStyle(QWizard::ModernStyle);

src/mainwindow.cpp

@@ -1641,6 +1641,8 @@ bool MainWindow::readOptions()
     if (!initialGroup.exists() || KdenliveSettings::sdlAudioBackend().isEmpty()) {
         // First run, check if user is on a KDE Desktop
         firstRun = true;
+        // Check color theme
+        ThemeManager::instance()->initDarkTheme();
         // this is our first run, show Wizard
         QPointer<Wizard> w = new Wizard(true);
         if (w->exec() == QDialog::Accepted && w->isOk()) {