All asking virtually the same thing, and delivered now (command-click the script on Mac; not sure what it is on Windows)... but... only if the sub-script is in the same file.
Requesting this be added so that when doing the same on a subscript that's in another file it opens Script Workspace for the other file (if not already) and shows the script, just like it does for same-file scripts.
There is also the issue of scripts being open in their own windows, other than in Script Workspace. This can come about when a script is opened from the debugger, or when you've specifically right clicked on a script and selected "Open in New Window". The command-click (or the corresponding whatever on Windows) on a sub-script (the selected script in a Perform Script step) doesn't seem to work then either. So this idea requests that work also.
Finally, with FM17 now we have the option to perform a script by name. This idea also requests that command-clicking (or the corresponding whatever on Windows) on the named sub-script there, uses the same logic that it uses at runtime to decide which script is the matching script and open the matching script then as well.
I believe all these options should "just work" without any exceptions or complications for the user.