UPD2: The same mark appears when purchasing a gift.

The preliminary conclusion is that celebrities will be able to create their own gifts in Telegram. The "Gift Studio" website is most likely created for these people and Telegram developers to view sales statistics and release new gifts.

So please, do not twist my posts. Not just anyone will be able to create their own gifts in Telegram.
And the stickers... Forget it.

Information about new updates is provided after detailed study and understanding of how it works.

@telelakel