title: Bootstrap 3 modal background is missing
body: <p>The Bootstrap 3 modal normally makes the page darker to highlight the modal itself, and to signify that the page UI is disabled while the modal is showing.</p>
  
  <p>At some point during my coding (a few weeks ago), the background stopped showing up. Everything else works fine, including closing the modal by clicking off it or clicking the X in the top-right corner. The page UI is also disabled until the modal is closed, which is fine. Since it's thousands of lines of code, I won't paste them here.</p>
  
  <p>I can't figure out why my modal background is missing. I have validated my HTML to make sure there are no missing tags. I am also using datatables, tabdrop and d3 on my page but have tried removing these (JS and CSS) one by one to resolve the issue to no avail. What else should I check?</p>
  
  <p>Here is the page: <a href="http://suite.swiftdigital.com.au/scripts/marcus/modal/event.htm" rel="noreferrer">http://suite.swiftdigital.com.au/scripts/marcus/modal/event.htm</a></p>
  
  <p>Click on the green "New Participant" button to see one of the modals. Another is the Edit View button in the middle of the screen.</p>