I added a structure 3 column to my site. In each column I put a modal bric. I can see the modals in the work area, but when I preview or export they do not display.
The modal will only display when you click the trigger that opens it. If you have three modals on your page, you will need something like a button or text link to fire each of the modals. The “toggle modal” interaction works like an on/off switch. Clicking the trigger link will display the modal - clicking a second time will hide the modal.