hide option, if no quick access service is present

src/main/java/org/cryptomator/ui/preferences/GeneralPreferencesController.java

@@ -105,6 +105,10 @@ public class GeneralPreferencesController implements FxController {
 		});
 	}
 
+	public boolean isSomeQuickAccessServiceAvailable() {
+		return !quickAccessServices.isEmpty();
+	}
+
 	@FXML
 	public void showLogfileDirectory() {
 		environment.getLogDir().ifPresent(logDirPath -> application.getHostServices().showDocument(logDirPath.toUri().toString()));

src/main/resources/fxml/preferences_general.fxml

@@ -30,7 +30,7 @@
 			<ChoiceBox fx:id="keychainBackendChoiceBox"/>
 		</HBox>
 
-		<HBox spacing="12" alignment="CENTER_LEFT">
+		<HBox spacing="12" alignment="CENTER_LEFT" visible="${controller.someQuickAccessServiceAvailable}" managed="${controller.someQuickAccessServiceAvailable}">
 			<CheckBox fx:id="useQuickAccessCheckbox" text="%preferences.general.quickAccessService"/>
 			<ChoiceBox fx:id="quickAccessServiceChoiceBox"/>
 		</HBox>