See the referenced Mozilla bug for details.
Should be fixed by the pending rebase https://bugzilla.redhat.com/show_bug.cgi?id=1386874
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory, and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.
This is _not_ fixed in RHEL 7.4 and I cannot reopen this bug report.
A year later and this bug report is still not solved.
Is it the same issue?