The user clicks "add general comment" and starts typing a long comment. During this process, the user moves the mouse such that it hovers over a line number which already has a comment associated with it. The hover causes a pop-up to be generated. This destroys the comment edit window and the text that has been typed is lost.
This is very annoying if the comment is long or detailed. There is no way that I can see to retrieve the lost text.
This bug occurs with 1.9.10 test build 1.