There is nothing called as permanent link in Telegram. Other clients mentions it as Invite link. But Invite link string will not suit here as just above this section, the page title is mentioned as Invite links.
Other suggestion is primary invite link, but in other places it doesn't mention Invite as part of the name. It is just new link, additional link etc
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Primaryublic link
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ICO,
Jun 14, 2022 at 10:42
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Other suggestion is primary invite link, but in other places it doesn't mention Invite as part of the name. It is just new link, additional link etc