I'll say sell a virtual Appliance (think GitHub Enterprise) for those who want to self-host. The truth is it's really hard for people to pay for what they get for free.

Open sourcing is an option but don't expect to make money right away - it's a longterm game.

I have some experience in monetizing open source, if you want to reach out. I developed osTicket (popular ticketing system) and ended up launching hosted version - which is doing well now. Was able to hire a team and we are profitable.