Originally made because I wanted to share a sticker pack with friends that weren't on Telegram.
Note: While I did make this with security in mind (all dependencies are included with the script itself) you should never run arbitrary code, particularly on Telegram. The best idea is to probably not use this. The second best idea is to get the code yourself, vet it, then run it locally. However, there is still a bookmarklet for your convenience.
This was mainly made for my own personal use. It has no affiliation with Telegram whatsoever. Use it at your own risk. Also, downloading the stickers doesn't give you the rights to use them in other places. If you really want to use Telegram stickers elsewhere, find the original artist of the sticker pack, and message them. Maybe you can even get the originals from them!