I made video but I don't know how to upload it here
But it isn't bug. Yes, you can move any elements using arrow keys. It is old our feature.
But, this prevents from what is expected as default behavior for arrow keys, which is just moving text cursor (at least during editing). IMO moving textbox in this situation is unexpected/unwanted. I'd consider to move "move textbox" feature to ctrl+arrows or using just arrows, but never in text edit mode - for example, when you have just focus on the textbox, but you don't edit the text yet.
Ok, we will think.
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