I tested the reported scenario and I was not able to reproduce the issues. The tabs and the backstage or opened correctly even if the RadDatePicker is focused. Can you please send me code snippets or a project with an isolated implementation that recreates the issue? Also, steps to reproduce will be helpful. This way I will be able to test this behavior locally and investigate what is causing it.
As a side note, keep in mind that RadRibbonView and its components are design so that they don't get the focus when you interact with them.
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