Reminds me of the #amiga editor CygnusEd :amiga:
https://youtu.be/IOkMQS0-qr0?t=3580
The reviewer seems to be using a horrible deinterlacer with his physical Amiga 1200, which ruins the smooth scrolling effect.
The editor also feels more sluggish than I remember it on my slower Amiga 500, perhaps because the reviewer switched to a Workbench screen with too many bitplanes?