DeFi Protocols on Different Chain

[GreatArkansas]

I am wondering how some DeFi or non-DeFi related platforms are available on different chains?

Let's say I am on the Ethereum network, I am using x platform, is every transaction on y network will also be available to other networks where the platform is supported?
I am curious how they are aligned together, especially I saw a lending platform where it seems the interest is the same as other chains supported.

[lobo13hf]

These DEFI were deploying multiple platforms into the various chains and make defi can support multiple chain at once. I take https://ftm.curve.fi/ as an example. If you wanna try to create a transaction in another chain and then you should move to the another network and in here the domain will be changed as well. The transaction that happened in Y network like what you have mentioned above (ethereum) will not be available in other network even when this defi were supporting all of compatible network to the ethereum.
Every transaction will available in Y network and it will not available in another supported chain by the defi platform. CMIIW

[tbct_mt2]

DeFi projects can use Multichain.org tool to create Cross-chain Routers. There are risk from bridges like the terrible hack with Ronin bridge.

I would prefer to talk about another thing, regarding total supply. When a DeFi project on ERC-20 chain want to bridge to BSC or any chain, you should check that whether that project burn the correspondent supply on ERC-20 chain. The burn is necessary to keep its total supply unchanged.

Scam project can bridge to a new chain and does not burn the correspondent amount of token in the initial chain. It is like double their total supply on two chains, minting new supply from thin air.

[GreatArkansas]

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Thanks, guys, I really love your explanations especially on @tbct_mt2 about how the bridge works like burning on the origin chain and producing coins to the destination chain, and yes, there is already lof of cases about hacks about bridges even before.
I am also curious if for example the X chain platform was hacked, is it also guaranteed that other chains where the platform deployed could be also affected or get harm at the same time?