@Don Von Alpha Dom
Sure have. I've made a Canned Responder for it before, still have that actually.
Gave you the option of having 4 responses customized and saved them. So you could click a button and it would make IMVU the active window before sending whatever chat response you previously saved, to the chat room. Would also let you customize the button text too. All that was saved to a file for persistence between use. It was restricted to a single room, by the window title, but that can easily be removed to make it work with any room.
Also made a multi-line text poster years ago that would accept a hotkey press when on a certain website (optional to avoid accidental activation), wait for text to be copied to the clipboard by the user, then activates imvu as the current window and posts each line of the clipboard in rapid fire succession until complete, before restoring the clipboard to previous contents. I made it at the time for sending ASCII art to the chat for fancy text images, but ofc could be used for ill intentions as well lol.
I've made other stuff, but it's been a long while so it's not coming to mind at the moment haha. That or it unfortunately got lost in the sands of time.