… email conversation with Sensible Software legend Stoo Cambridge, and …
Nice that the solution for this is so trivial, if you want it. Always a bit of a security concern though with these venerable old file formats (and certainly, no modern machine wants the colour palette in interleaved bitplanes) where the loading technique was generally ‘map it into memory, and treat it like a struct’. ILBM isn’t as complicated as eg. TIFF, but buffer overruns and pointer shenanigans in dusty code is something to be wary of - I wouldn’t want this enabled by default