Created attachment 222403 [details] Screenshot of Sonarr complaining about Mono version Sonarr reports in the latest version: "Currently installed Mono version 5.10.1.57 is no longer supported. Please upgrade Mono to version 5.20." Please change the dependency in net-p2p/sonarr-devel from mono-5.10 to mono-5.20. Thanks.
Mono 5.20 has never worked on FreeBSD. There is work to get Mono 6.x but it has stalled out. The history is here: https://reviews.freebsd.org/D23300 I can't provide more details or guidance, but this is beyond the scope of this port/package.