Super Resolution making strange block artifacts

[jogomu]

Reporting the attached behavior.  Also noticed some increased color fringing of specular highlights, e.g. to lower right of cat's left eye.

Raw file (block artifacts created above cat's head):

https://www.dropbox.com/s/9iyjj0duwvnn83q/2021-03-28%2013.31.47.raf?dl=0