To reproduce: this.radTextBoxControl1.Text = "dog and blue glue"; this.radTextBoxControl1.Size = new Size(50, 65); this.radTextBoxControl1.Multiline = true; Workaround: use RadTextBox.
Hello,
I have reviewed this case using the latest Q4 2025 version (2025.4.1111) of the Telerik UI for WinForms suite, and the issue does not reproduce. The whole text gets selected:
I am closing this item and setting its status to "Declined" on our feedback portal, as the issue does not reproduce anymore. Please upgrade to the latest version to take advantage of the improvements in the RadTextBoxControl: How to Upgrade Telerik UI for WinForms Project - Telerik UI for WinForms
If you have any other questions or concerns, please let me know. Thank you!
Regards,
Nadya | Tech Support Engineer
Progress Telerik
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