The Application layout » Dockable windows branch of Settings has the following options.'
This field is used to specify the number of milliseconds of delay before auto-hiding dockable child windows (i.e., those in the Layout tab) are auto-hidden upon focus change.
The slider here can be used to adjust the animation speed used to close a child window when set to auto-hide. If the slider is moved as close as possible to "Disabled," the animation will be very fast. As the slider is adjusted more towards "Smooth," the animation will slide out of the edit window space more gradually.
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