As claris/filemaker does its best to hide these links, here is a direct, non authenticated URL to download Filemaker Server 19/20 directly from Filemaker. Beware, their servers are slow.
- https://downloads.claris.com/esd/fms_19.5.1.43_Ubuntu18.zip
- https://downloads.claris.com/esd/fms_19.5.2.201_Ubuntu20.zip
Ubuntu was killing me with incompatibilities with NVIDIA, while Mint Debian works great, no problems since I change the system. I will keep Mint Debian... thanks a lot anyway!