iFrame works until I turn on developer tools in Safari then it stops workin

I have a iframe that works unless you turn on developer tools. I did not set anything except for going to file, set preferences and check the SHow Develop menu in menu bar, then the iframe fails. Now if I turn it off it still does not work, but if I go to another mac that has the same version of safari it works fine as long as they have not done the above. It just does not make any sense to me. The iframe works fine is all other browsers as well on the Mac and Windows.