Revert "Fix setActiveWindow deprecation warning"

This reverts commit 30024ac.
Due to bug described in #745

src/mainwindow.cpp

@@ -3918,7 +3918,10 @@ bool MainWindow::eventFilter(QObject *object, QEvent *event)
     }
     case QEvent::ActivationChange: {
         if (m_editorSettingsWidget->isHidden()) {
-            QWidget::activateWindow();
+            QApplication::setActiveWindow(
+                    this); // TODO: The docs say this function is deprecated but it's the only one
+                           // that works in returning the user input from m_editorSettingsWidget
+                           // Qt::Popup
             m_textEdit->setFocus();
         }
         break;