Comment 11 for bug 68040

I also believe this to be a major blocker for mozilla. Try to explain to my
father, who knows very little about computers, that mozilla is better than IE
but he still has to lauch IE to access is homebank account.
showModalDialog() is a de facto standard. If there is even a comment that says
it is that same that using window.open() with dependent=1, then the code to
support it is already, just need to change the parser so that when it finds the
showModalDialog() reacts the same way as parsing window.open() with dependent=1.