An algorithm element can be moved around on the Scene by dragging it and can be resized by dragging its borders.

But if some constraints are imposed on the element, then the element can only be moved / resized within the bounds of the constraints.

On the image below you can see constraints highlighted in green when an element is moved:

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     <img src="/wiki/download/attachments/4686218/Resizing and Moving Algorithm Element.png"/>
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