Text file which contains character code >127 is treated as binary files when it's added to review using REST addFile. That causes "Download revision ..". link to appear instead of text to be displayed.

As workaround file content type 'text/plain' can provided during file upload. Which means instead of

curl -v http://localhost:6060/foo/rest-service/reviews-v1/CR-1/addFile -u user:password -F "file=@CU94745.CBL"

we can use

curl -v http://localhost:6060/foo/rest-service/reviews-v1/CR-1/addFile -u user:password -F "file=@CU94745.CBL;type=text/plain"

. Note ;type=text/plain difference.