So I shared an emoji with someone in the DM, then on Tweetdeck it shows the link to the emoji. I clicked it. It shows the full URL of the emoji file.
I thought to play about with the numbers, and what I learnt is that 10012 is the image file number, while 128 is the file size. So if you change to 10013 you have another number and if you change to 64, 256, 512 or 1024 you get a different size.
Knock yourselves out.