Currently the RadDocks that are placed in a RadDockZone can be resized only in the boundaries of the dock zone. For example, if you have a dock in a vertically oriented dock zone and there is space below the dock, you can grab only the bottom handle to resize it. This can be examined in the online demo Dock Resizing
Including such functionality is not planned at the moment. Nevertheless, you can log the feature request in our Ideas & Feedback portal
by describing it in detail and we will consider implementing it if it becomes popular.
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