Reset webdavport field if changes are not applied and focus lost

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

@@ -48,6 +48,11 @@ public class VolumePreferencesController implements FxController {
 		webDavPortField.setText(String.valueOf(settings.port().get()));
 		changeWebDavPortButton.visibleProperty().bind(settings.port().asString().isNotEqualTo(webDavPortField.textProperty()));
 		changeWebDavPortButton.disableProperty().bind(Bindings.createBooleanBinding(this::validateWebDavPort, webDavPortField.textProperty()).not());
+		webDavPortField.focusedProperty().addListener((observableValue, wasFocused, isFocused) -> {
+			if(!isFocused) {
+				webDavPortField.setText(String.valueOf(settings.port().get()));
+			}
+		});
 
 		webDavUrlSchemeChoiceBox.getItems().addAll(WebDavUrlScheme.values());
 		webDavUrlSchemeChoiceBox.valueProperty().bindBidirectional(settings.preferredGvfsScheme());