Content stays locked even second user quits editing it
Common habit is to cancel screen by hitting X in upper right corner.
If second user does so doing frontend editing to some content using rtehtmlarea the announcement that he/she has started editing stays for ever (until he/she has logged out from the same content some how; hard to find this method)
This effectively prohibits simultaneus content editing.
Linux/CentOS 4.4 (updated per at moment)
Browsers: Firefox 2.0.x and Opera 9.10 and IE 6/7
(issue imported from #M5130)