I have tested all the cases mentioned in the comments on Linux Mint 17.1 Rebecca 64 bit with Python 3.6.0a0 build version.

1.I reproduced the issue mentioned in #msg241871 the minimize button works perfectly fine and the search dialog box does minimizes(Which implies that this is a windows only issue).The maximize/expand also works and the dialog window can be resized both horizontally and vertically.

2.Similarly, 'Find in Files' and 'Replace' dialogs can also be resized and have both maximize and minimize buttons which too work fine.

3.The 'Options' => 'Configure Extensions' dialog does not have the maximize/minimize buttons but it can be resized.

4.The 'Options' => 'Configure IDLE' dialog can neither be resized nor does it have maximize/minimize buttons.