JPEG strips come out clean (v0.27.3) · Sprite Manager devlog

Strips are drawn on a flat magenta background that the pipeline cuts away. A JPEG, which Gemini hands back, blurs that magenta into the strip's outer rows, and the first CHEF! counter front showed a thin purple line along its top and bottom.
The cutter now trims rows that are magenta blended into the edge, not only pure magenta.
A new tool rebuilds an already accepted file from its untouched upload after a fix like this, and can correct which generator the records say made it.