Telegram desktop app: In the upper left corner, click the Menu icon (the one with three lines). Select “New Channel” from the drop-down menu. The optimal dimension of the avatar on Telegram is 512px by 512px, and it’s recommended to use PNG format to deliver an unpixelated avatar. Image: Telegram. Content is editable within two days of publishing 2How to set up a Telegram channel? (A step-by-step tutorial)
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