Create a control (e.g. button).
Create an action script for it (anything will do)
Save that, then choose “edit script”.
If you try to “copy” (cmd-C) a part of the script, or even select it all (cmd-A), you get a dialog question
Delete Actions?
This object script was created by an action set, changing the script will cause the action set to be removed.
Are you sure you want to do this?
but these operations (cmd-C, cmd-A) do not change the script - so this question is unnecessary.
And in fact, worse than that, if you really do want to copy a section of the script, and therefore respond ‘Yes’ then the script is marked as ‘changed’ and any subsequent actual change will happen without questioning.