Edit the /components/com_jfbconnect/assets/jfbconnect.css file. In there, you'll see:
.fb-comments, .fb-comments iframe[style] {
width: 100% !important;
}Update that first line to:
.fb-comments, .fb-comments >span, .fb-comments iframe[style] {That fix is already implemented in our code and will be in the 5.1.2 release scheduled for next week.
I hope that helps,
Alex