Hi there, I'm a little new to lttng and tracing in general. I am using a Java Userspace agent, which is working well, but I am having trouble adding callstack context to my tracing channels. I'm not sure if it's relevant but running 'lttng add-context --list" shows callstack-user in the list. the commands I input are: lttng create lttng enable-channel --userspace mychannel lttng enable-event --userspace --all --channel mychannel lttng add-context --userspace --channel mychannel --type callstack-user >Error: callstack-user: UST invalid context When I run the following command instead: lttng add-context --userspace --channel mychannel --type vpid I am able to get it to work and I see vpid appear in my traces. Are there any other things I need to set up first to be able to use it? also, are there any commands that can list the per-domain contexts available?