Comment 17 for bug 231628

Here are the steps to reproduce the problem.

1) Log onto gmail.
2) Click "Compose Mail" with <shift> held down so that it forms a new window.
3) Maximize the new "child" window.
4) press <ctrl>+ to make the text bigger in the "child" window.
5) see that the content in the "parent" gmail window has changed as well.

This seems to only happen when there is a "child" window spawned from a "parent"...
  the parent for some reason is updated with its child!
It is very annoying for a gmail user.