In changelog for version 1.14.0 we have many enhancements for mupdf-gl, but it not installed any more.
It is not being built, and I need to look why.
Thank you for reporting.
A commit references this bug:
Date: Sun Feb 24 18:39:44 UTC 2019
New revision: 493796
graphics/mupdf: fix mupdf-gl not being built.
Reported by: Oleh Hushchenkov <firstname.lastname@example.org>
Approved by: tcberner (mentor)