Attempting to setup a Gerrit server using a ed25519 key, it returns the following error message:
"/var/lib/jenkins/.ssh/id_ed25519" is not a valid key file."

I've tracked the problem to originate in the

com.sonymobile.tools.gerrit.gerritevents.ssh.SshUtil.isPrivateKeyFileValid

method, which is from the (apparently) bundled gerritevents library.