This is an archived snapshot of W3C's public bugzilla bug tracker, decommissioned in April 2019. Please see the home page for more details.
Open a new document. Type: "first line", then insert a <br> with Insert->Break (br), then type "second line". Place the cursor at the end of the first line, and insert another break. At this point, the cursor has disappeared. Alas, place the cursor at the beginning of the blank line between the two, and type a character. You will see that the break disappears and the character, is immediately moved at the end of the previous line.
That problem is now fixed.