
I can reproduce your issue but it looks like something inside the libheif library. I don't have time to look at this for a while. I will try to upgrade libheif in ImageMagick to test if that fixes the issue in a couple weeks.
Not a show-stopper. Thanks again for your continued support!
Updating libheif to vewrsion 1.6.0 did not seem to resolve the problem. Will need to do some more investigating.
I don't know if it is relevant, but the original submitter claimed the images could be viewed using Windows Photo, after having installed the "heif image extensions from microsoft store".
Reported this upstream. Will now need to wait for an answer.
This issue should be resolved in the latest release (7.15.0.0).
Thanks a lot!