Comment 6 for bug 398880

With what application does this occur? It looks like the first time you click, you're clicking on an application that has a PID of 0. That will never work, and that is a bug in the application (or the application is _extremely_ old and predates all current desktop standards; still, that means that the application needs to be updated).

Are you clicking on the window proper, or are you clicking on the window decorations? And for the process that you're attaching to in the second attempt, is that the same application? If so, what is it?