Hi!
This is kinda possible.
I say kinda cause the 2 ways i can think are not exactly a pop-up image.
#1
You can open a picture window
And then use /drawpic to print the picture on it.
And finally with a timer close that window after some seconds/miliseconds.
Do /help /drawpic for more detailed about it's usage
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#2
You can use a dialog.
Do /help dialog
You can make the dialog have one icon control and then put the pictue there .
I think this option fits your neefs better because it will look more like a pop up and not a whole other window. You can make a dialog have as much width and height you want.
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I hope i helped.. let me/us know if you need more help
