Created attachment 211902 [details] enable option ASS by default libass is necessary for subtitle operations, and this is an very important feature for non-English speaking area. The attached patch enables option ASS by default.
I'll commit this as there seems no objection.
A commit references this bug: Author: lwhsu Date: Wed Mar 11 08:06:53 UTC 2020 New revision: 528216 URL: https://svnweb.freebsd.org/changeset/ports/528216 Log: multimedia/ffmpeg: enable libass by default libass is necessary for subtitle operations, and this is an very important feature for non-English speaking areas. PR: 244377 Changes: head/multimedia/ffmpeg/Makefile
Maybe also enable ASS in multimedia/vlc. After that there would be no non-default consumers as multimedia/mplayer and multimedia/mpv already enable ASS while the rest are unconditional.