I've described this problem already here: https://avalondock.codeplex.com/workitem/16060 and proposed a solution. Please review it.
A have one main docking manager and nested docking manager is displayed as document (in document tab in) main docking manager. If I close document, AutoHideWindow will never be disposed and this is memory leak.
A have one main docking manager and nested docking manager is displayed as document (in document tab in) main docking manager. If I close document, AutoHideWindow will never be disposed and this is memory leak.