The fact that it is a 2-of-2 multisig is relevant only because the UTXO - that is actually the channel - must be spendable only if both parties agree on that or some other conditions are verified (like in force closure).
The onchain broadcasting actually happens automatically once you or the counterparty decide to close the channel, which can happen whenever you need to (that is the game theoretical assumption behind the security model of LN and the reason why it is actually a self sovreign protocol).

Xactly. My intermediate level of English doesn't give me a chance to describe what I want. 
I know that LN is 2of2 multisig under the hood. I wanted to know about opportunity to broadcast it

030e0dca83

I think you do not understand what is LN and how it works.
LN IS on mainnet. Is actually just not-yet broadcast onchain txs.

DarthCoin

No. Not like that.
Use the 3 levels stash method: hodl, cache, spending (LN).
So sats from SN you should pass them through a cache level or swap service, then into a hodl wallet.
[![3level-stash.jpg](https://i.postimg.cc/MTL2kvT0/3level-stash.jpg)](https://postimg.cc/vg5Sf85D)

Read those guides I posted above and also these one:
- https://darthcoin.substack.com/p/bitcoin-be-your-own-bank-think-like
- https://darthcoin.substack.com/p/stacking-sats-noob-journey

![1000005047.jpg](https://m.stacker.news/20158)
I mean add here button "send it to my segwit wallet"

What do you mean by that?

If you mean swapping Bitcoin on Lightning for Bitcoin onchain, that service already exsists e.g. from https://boltz.exchange/