The most evident:
• maximum number of pinned chats - 5
• you can edit the message within 48 hours
• you can invite up to 200 people from one account to the channel
• maximum upload file size is 1.5 GB
• subscription for a maximum of 500 channels
Rare ones:
• up to 200 groups and up to 8 channels can be registered per account
• username size - from 5 to 32 characters
• if the number of subscribers of a public channel is more than 1000, you can delete such a channel only through technical support
• up to 200 stickers can be installed
• telescope (a video message) can last up to 1 minute
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