To upload a logo, click the Menu icon and select “Manage Channel.” In a new window, hit the Camera icon. To delete a channel with over 1,000 subscribers, you need to contact user support 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. How to create a business channel on Telegram? (Tutorial)
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