flash videos with firefox 4 beta and lucid do not respond to mouse clicks

[Tapas Mishra]

As per the instructions given on
http://www.liberiangeek.net/2010/07/install-firefox-4-0-beta-ubuntu-10-04-lucid-lynx/
I upgraded to latest firefox since I am unable to have videos being
watched on firefox in my system.
I disabled
dom.ipc.plugins.enabled
from "false" to "true"
also disabled Ubuntu firefox modifications
and there are no plugins installed.
I had a similar problem in an old version of firefox have asked on this lisk
http://old.nabble.com/arrow-keys-not-working%28some-times%29-when-I-am-using-Firefox-page-up-and-page-down-also-is-not-working%28some-times%29-Ubuntu-10.04-64-bit-Firefox-3.6.8-td29615707.html