The Properties tab includes all the properties inherited by the widget from its parent web part. Please see the help topic of the web part Properties tab to learn about the options available when configuring properties.
Using the Display attribute in the editing form checkbox, you can choose if a given property should be available to users in the widget configuration dialog. If the Display attribute only in the dashboard box is also checked, the property will only be accessible when configuring the widget on one of the dashboard sections located in the CMS administration interface.
Please bear in mind that any changes must be confirmed by clicking the Save button at the top.
More resources can be found in: