Following up on this case, it appears that this is a known issue which we already have in our feedback portal: http://feedback.telerik.com/Project/154/Feedback/Details/110711-fix-radtextbox-text-is-cut-from-below
As you can see in the description, the workaround is to set a MinimumSize
to the inner text box. You can also see how to use TextMeasurer to measure the height of the text so that the text box sizes correctly with all fonts.
I hope you find this useful. Should you have any other questions, do not hesitate to write back.
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