Hi, I just upgraded to 2.9.8.4 and I am having the same problem. I put in all my bootstrap slide info and everything works. I can even make changes to the slides until I exit the customize menu and go back to the normal WP menus. Once I exit the customize menu and then get back in to the customize menu again and try to edit a Bootstrap slide, all the slides and info are gone…even though they are still appearing on the site. Whats more is that if I make any other customization to the site and publish it, all the slides will disappear from the live site.