I dunno if it is hard to get this to work. All which is required is to check on the user's email address, which is very basic JScript.
Of course, it depends from script to script where this is done.
eg: in that other thread, it was said to add the check in each function of the script. This is however not required. You only need to place the check in the main function(s) of your script; the function which drives all other functions.
So in the end, all what is required is a small bit of basic knowledge of how JScript works and an understanding of the logic/workings of your own script. Then place a check in its main function. But you need to have that basic knowledge anyways to make a script in the first place.
But I understand your concearn. Though this concearn is only present with people who don't have the basic knowledge yet to script (no offense). Once you gain some experience (which will come extremely quick), you'll have no problems with it.
As you can see in your other thread, in the end, the solution is very simple and very logic: before starting to replace each emoticon shortcut, simply check if the current user (Messenger.MyEmail) is the one for which this script should be executed.
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