I tried to reproduce the reported issue, but to no avail. You can find attached my test page and a screen capture
that shows the RadDock's behavior on my end. Please check them and let me know if I am missing something in order to recreate your scenario.
The behavior you described could be a result of applying custom CSS styles to the RadDock controls. Are there such styles and if there are, is the problem examined when you remove them? Note that these may also be global styles that are applied to the HTML elements of the docks.
Note that I am guessing as to what your full setup is. If possible, please modify the attached page in order to reproduce the issue. You can also create a simple, fully runnable project that isolates the problem so that I can inspect it on my end and provide a more to the point answer.
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