I think I understand this now.
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37AATGG5QIXOBXWA3DMSVMIIDSULA36NPETHOYZIOZ4G4RZLMHCAC
KKMFQDR43ZWVCDRHQLWWX3FCWCFA3ZSXYOBRJNPHUQZR2XPKWULAC
-- the editor widget thinks the screen is small and can scroll overly much
-- the editor updates screen_top1, then we update viewport based on screen_top1, and it goes from somewhere lower down to all the way at top of screen