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Clip to Canvas is not available as an option when you have Artboards as layers outside of the Artboards should be visible anyway, unless they are visually obscured by Artboards or other layers.
A layer, when it is in an Artboard, whose boundary is only partially inside the boundary of that Artboard, will only be partially visible and, I believe, that is expected behaviour for the software because of how Artboards are supposed to be used.