bug on edit comment

hi
tested on easysocial demo site http://easysocial.stackideas.com/

step by step
write and submit a comment ,
click to edit ,
click on the back space key (on the keyboard) or the delete key and hold it to delete all the words ,
it will delete the words but the words back to show again (untill now you hold the key) ,

please try to delet all the comment and dont leave the key .

thank you