Our Readme file for InterMapper RemoteAccess is in error. Sorry if you installed Java 8 as a result. If you don't use it for anything else, please remove it.
Our installer contains OpenJDK 11 which we'll use to run the IM RemoteAccess client. If you defined any environment variables to point to Java 8, please also remove those.
I run IMRA 6.5 on Ubuntu 18.04 on one of my test VMs, and it works fine.
I've filed a defect report to get the reference to installing Java removed from the Readme. Again, our apologies.
If there is any further issue getting up and running, please email firstname.lastname@example.org and we'll help get it sorted out.