Thank you for the sent screenshots.
I've tried to reproduce the overlapping of the RadRichTextBox's ContextMenu and the SelectionMiniToolBar controls, but to no avail. The only way I've achieved this was during resizing (shrinking) the window which hosts the RadRichTextBox when the mentioned controls are already shown. Since this cannot be avoided, you could invoke the Hide() method of the ContextMenu and SelectionMiniToolBar when the size of the host control has changed.
For your convenience, I've created a sample project which illustrates the approach described above. You can find it attached.
However, if this is not the case, please try to modify the sent project in a way the issue can be observed and send it back to us. In this way, it will be much easier for us to find what might cause the undesired overlapping and try to solve it.
Looking forward to your reply.
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