This page is for developing the Popup modal.
Because the modal is a Symbol that appears on every page, the root div 'modal' has the display attribute 'display-none' as its default (otherwise it gets in the way of content on the page). The code controlling the popup when the page loads overrides the 'display-none command.
To view the modal for further development set the div called 'modal' to 'display'.
This message is not part of the modal.

To temporarily disable the popup if not required (but could need it at a later date), select the Interaction from the list on the right and set the second setting called 'modal' to None, or display depending on what the need is.