Open the http://www.copyn.plus.com/mozTest21.html and you will see a drop down selection and a checkbox beneath it. Try clicking on the checkbox - it appears not to respond. If you look at the source there is an absolutely positioned hidden iframe that is causing the problem. My investigation has revealed the following: 1. click the checkbox an odd (as opposed to even) number of times and then change the drop down selection. When the drop down disappears again the results of the check box change are revealed! 2. Make the IFrame have height & width = 0 and the problem goes away. 3. This was new sometime after release 0.9.1 and I have confirmed the problem in build 2001080104 in Linux and build 2001073017 in Windows NT 4.0 Sorry for yet another hidden iframe bug - but they really are very useful!

over to compositor

my checkin for bug 100652 fixed this. Marking fixed.