told ya it isnt possible and if it's possible you fuck up every pc that doesnt have the plugin, because the image will be (if you don't have the plug) frames*heigt or worse frames*width, this will fuck up his conversationwindow...
but when you're this far there may be 1 thing worth trying:
send a command (at the background ofcourse) (before sending the avatar) 2 see if the other has the plugin installed, the problem is that i dont think it is possible with a standard messengerplus, so 4 this you must be able 2 change the conversationwindows like an Add-on
...
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