The Arc-theme have a new upstream again, disabled cinnamon as an option because the current version in the ports of it is unsupported & openbox option have been remove because it have now its own repository.
Changelogs: https://github.com/jnsh/arc-theme/releases/tag/20200513, https://github.com/jnsh/arc-theme/releases/tag/20200819, https://github.com/jnsh/arc-theme/releases/tag/20201013
Related to [[https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=247745|PR247745]]