Thanks @Taddeusz, no hurry it's really a minor inconvenience. In this scenario where would be the correct location to add the plugin? As I mentioned if I add it to the extensions folder in the volume on appdata it is removed on container startup with a message about updating the plugin. Should I instead place it in the '/opt/guacamole/quickconnect/' location so the startup process finds it there? In this case it would disappear on container updates. I'm more than happy to just put the jar files in a mounted volume myself, the problem is more that during startup the container seems to remove any manually added extensions.