"helloWorld" is a function that writes "Hello World" and is an example function.
@Znevna was able to reproduce the error.
I leave this other script (module-continer) as an example, it creates a global function "registerContainer", the function works perfectly, the problem is that after 5-10 minutes the global function disappears from the environment.
One thing you can tell is a ROS bug is that the script's run-count read-only variable returns to 0 when it should indicate it has > 1 runs.
/system/script> :put [get hello-world run-count]