Download patch
ref: 6a6ba10315baf4b0092c6d952a2f0cb502b6ac8e parent: 5a5f5ececdde2c4c62bdee649d8b1d3edba96fed author: Rangi <remy.oukaour+rangi42@gmail.com> date: Sat Mar 21 10:01:05 EDT 2020
rgbds supports 'X - 1' instead of 'X + -1'