Thank you for your feedback. Indeed, we have discussed this behavior here, becuase the area where the sizing grip appears should be larger. The task is logged and we will improve the behavior soon.
I have updated your Telerik points for sharing your observation. I am afraid there is no workaround I can suggest at the moment.
Do not hesitate to contact me back if you have more questions.
All the best,
the Telerik team
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