i run into the same issue. it should be a feature – but its a bug ??
as mentioned on the plugin details:
New comment system (Like Facebook) – A member can write a new comment just by typing a comment and pressing Enter to send or Esc to cancel.
but it seems, that the javascript for “just pressing enter” requires jQuery below 1.9 because of the usage of the “.die”/”.live” functions, which are deprecated. So an error occurs when you have a newer jquery version on your site
//remove event handler previously attached to #bpfb_submit
jq("#bpfb_submit").die( "click" );
that causes an js error which stops executing the other js (including the press enter to submit function)
TypeError: jq(...).die is not a function
there are a few workarrounds for this:
1. what you found: uncommend the inputs, it will work, hope the best for the next update…
2. load an older jquery version in your blog (can cause other complications), but its possible to have 2 versions of jquery running (https://stackoverflow.com/questions/1566595/can-i-use-multiple-versions-of-jquery-on-the-same-page)
3. inform the plugin developer (should be done whith this thread)
todo for the plugin developer: turn all “.live” functions into “.on” and all “.die” functions into “.off”
see https://api.jquery.com/off/ vs https://api.jquery.com/die/