In this specific scenario, we have a menu with 2 menu items: &File and &Open. The mnemonic sign is set to the F and O letters. In the form, we have a TextBox control which is currently focused. The next step is to press the Alt key while the TextBox is focused. Pressing some other letter, D for example, the letter will be typed in the TextBox. This letter does not exist as a mnemonic, and the RadMenu will ignore it. The RadMenu remains in active mnemonic state.

Expected behavior: Using none mnemonic letter should not be accepted by any other control until this state is closed in the RadMenu.