The Channel name and bio must be no more than 255 characters long To edit your name or bio, click the Menu icon and select “Manage Channel.” Telegram Android app: Open the chats list, click the menu icon and select “New Channel.” 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. 2How to set up a Telegram channel? (A step-by-step tutorial)
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