@mwichary how common is the pattern of a combined arrow key, like here on a Xerox Alto keyboard?pic.twitter.com/GrJ02mFYKL
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But as per the above image, I am not sure this is a cursor key. It seems this might just be two arrow characters sharing one key. (Funnily enough, C64 also had one of them.) Those seemed pretty uncommon to me.
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