How to add a custom TLD?

I've assigned domain names using a custom TLD to my home servers for ease of access.

When I put, say proxmox.server, in my address bar, it searches the web. To avoid that behavior, I have to specify http://proxmox.server.

I want Firefox to recognize .server as a valid TLD. I've searched the web to no avail, so that's why I'm writing this.

I came across this post in Stack Exchange, but the method described (ie, network.IDN.whitelist.server) doesn't work.

Does anybody know how can I add a custom domain to Firefox?

EDIT:

@[email protected] pointed out that there is a way to add nonstandard TLDs to Firefox: browser.fixup.domainwhitelist.yourdomain.yoursuffix.

It works, but a FQDN (with the imaginary TLD) is needed, that means it's not possible to whitelist all domains under a custom TLD. You need to add one entry per domain, that is: whitelist server1.mystuff, whitelist server2.mystuff, and so on.