https://bugzilla.redhat.com/show_bug.cgi?id=1035486
--- Comment #45 from Pierre Ossman ossman@cendio.se --- Impossible to test as bug 1545149 made it impossible to get Cantarell of any version to render sharp.
The end result (Cantarell being fuzzy) is still present in Fedora 28. But the cause is now either both bugs, or just the other.