The token list is managed by a separate smart contract. When you list a new token you send a payment transaction to the Token List smart contract containing the information about your token (the transaction is prepared for you automatically, you just have to click "Pay"). Ones the token is added to the Token List it will appear in the Token Catalog and users will be able to deposit the token to the main smart contract. Tokens that are not registered in the Token List contract cannot be deposited to the main contract as the main contract checks whether the token is present in the Token List contract.

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