This module shows how to make a repeatable param for a CMS Widget
Magento doesn't make this feature available on core and we must force serialization before Widget save. In order to do this we must check each widget param's name and (only valid in this example) should contain "repeatable". You can freely copy this module and change it's content for your amazing repeatable widgets! ENJOY!
Contributions are very welcome. In order to contribute, please fork this repository and submit a pull request.