I have noticed that I need to perform clicks multiple times if I want to close some window e.g. Firefox or even to close a tab. It happens frequently but not all the time. When I use the Eclipse IDE, if I select attributes options from property explorer, a few button/drop-downs are click-able, whereas for others I click on the buttons but there's no response.
Is this a bug in OS X Lion?
Example of clicking on Eclipse IDE fails to respond, even I have pressed the dropdown button.

