What inference engine are you using for flash next?
It always detects its spelling mistakes, btw, but it worried me. It may turn 'rm -rf ' into 'rm -rf /' one day.
Almost certainly the problem is my config, not the image.
Qwen Flash Next is just excellent, all the way to the very end of the native 262k context. (I haven’t tried YaRN scaling to 1M, so I don’t know about that.)