Will taproot-assets support increasing the total supply of assets

[youngzhenhao]

Will taproot-assets support minting additional fungible tokens with the same asset_id, similar to the ERC20._mint() in the future?
If not, how can I use taproot-assets to mint additional USDT tokens but transfer both the original tokens and the additional tokens in one single transactions?

[guggero]

with the same asset_id

The answer to that is no. The asset ID is a hash based on the asset properties, which includes an on-chain transaction to assert global uniqueness.
BUT the Taproot Assets Protocol introduces the concept of a group key (see https://docs.lightning.engineering/lightning-network-tools/taproot-assets/first-steps#docs-internal-guid-3bcd56b4-7fff-bfc0-8abd-da4246828716).
When creating a "grouped asset", the group key becomes the main identifier of that asset. Multiple so-called "tranches" of assets can then be minted into that group, with a signature using the group key proving ownership of that key. All those tranches would have different asset IDs but reference the same group key.

[youngzhenhao]

But the tapcli addrs new can only create address that is received with an asset_id, I can't use group key to receive multiple grouped assets.

[guggero]

Correct. That is a feature that we're working on, see #291.
But you can send assets from just a single asset ID within a group. But full group key support across all use cases (on-chain and within channels) is one of our next development priorities.