We upgraded Gerrit from 3.2.10 to 3.4.0 and this plugin stopped working.
We have been able to get some kind of error by executing "Test Config" from
"Manage Apps"/"Gerrit Settings" in Jira
`
Connection Failed!
An error occurred while testing the connection to Gerrit.
com.jcraft.jsch.JSchException: verify: false
`
It might be that the jsch version is too old and that it does not support the host key that Gerrit it using.
Gerrit changed ssh host key during the upgrade.