SyncHint

Contacts on your device
(phone
numbers, first and last names)
will be seamlessly uploaded to Telegram servers so you could find them in Contacts section of Telegram X, or receive a notification once they join.

When you delete a contact on your device while sync is on, it will also be deleted from your contacts list on Telegram servers.

You can always turn sync off or clear data on Telegram servers via Settings > Privacy and Security > Delete Synced Contacts.

To turn sync on, you also have to allow Telegram X to access contacts on your device.
Had to apply the English translation for the new text in a number of languages, please feel free to translate it
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