I carefully removed (but really quickly thanks to a regexp in vim)
every trailing whitespace from every file (except images).
Now,
$ grep -G " $" * -r
only returns images and
$ git diff --ignore-space-at-eol
comparing the changes I made to HEAD, or
$ git log -p --ignore-space-at-eol
does not print anything so I'm sure I haven't changed anything else.