It's not fixed and the same work arounds apply. You can find example code for handling this in the Known Bugs List database.
What you do is resize the original window using get functions to resize it to the largest "unmaximized" size that will fit your screen. Then you return your windows to Maximized state when the child window is closed--something that can be best automated with a custom menu where the close window option runs a script that both closes the current window and also maximizes windows, but that is only possible to set up if you are using FileMaker Advanced to develop the database. Note that this work around minimizes the window resize; it does not eliminated it.
Other developers avoid the maximized state, but I am less than thrilled with the resulting Window inside of a Window interface with the resulting added set of scroll bars.
Many thanks for info, i can seem to find the entry in the Known Bugs List though ??
I downloaded the latest version.
Thanks again for the help.
i can seem to find the entry in the Known Bugs List though ??
I gather you meant that you can't seem to find the entry?
The link dowloads a zip archive with both an .fp7 and a .fmp12 version of the same database. To open them and examine their design features requires extracting them from the zip archive before you open them.
Both the Find button found on the Main and Bug Reports layouts performs a script called "Open Search Palette" That you can find and open in Manage Scripts. You can also simply double click the button, click specify and then select Edit from the "gear" drop down if you have FileMaker 11 or newer.