New files created in the old Mac file format do not appear in diffs (BB-10156)

For testing purposes, I have to add DOS, UN*X and MAC file format.

When creating the pull request, the mac format file is not displayed. There is a place holder with the filename, but the content is missing. This is a new file. I am not sure of the behavior when a file is changed.

Also, the "Side-by-side diff" button is missing.