[shoo]

see also: squeezing 1024 colours out of a 1981 IBM 5150 with a CGA display:

https://trixter.oldskool.org/2015/04/07/8088-mph-we-break-al...

Explanation & pictures of how some of the techniques work:

https://int10h.org/blog/2015/04/cga-in-1024-colors-new-mode-...