Hi, Ashraf,
Thank you for reporting this.
Workaround: To trigger the DoubleClick event, you can subscribe to MaskedEditBoxElement.TextBoxItem.DoubleClick event.
Regards,
Nadya | Tech Support Engineer
Progress Telerik
Love the Telerik and Kendo UI products and believe more people should try them? Invite a fellow developer to become a Progress customer and each of you can get a $50 Amazon gift voucher.