Verified on Sat 6.5 Snap 14 using the reproducer from the initial report. Error page now uses Satellite grey color scheme.
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. https://access.redhat.com/errata/RHSA-2019:1222