The reasons why this can't be done. (tried to explain as clear as possible)
- Plus! can't interact with contact groups. I thought I heard that the API for it has some serious complications, like contacts in multiple groups etc. Of course you can let the user create a group of contacts and the script would save that array somewhere as a group.
- It's not possible to 'send' someone a toast message. What Hopper does is changing your nickname to the specified message, block those who don't have to receive the toast, quickly sign-out and back in to generate a sign-in notification and unblock the contacts again. It's not that it actually sends a notification to the users, that's what their clients do. And, when they disabled the sign-in pop-ups in the Messenger options, they won't see anything at all.
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