add polygon network to metamask
----------------------- Add Polygon (Matic) Network to MetaMask ---
MetaMask > Networks > Add Network:
Network Name: Polygon Mainnet
New RPC URL: https://polygon-rpc.com/
ChainID: 137
Symbol: MATIC
Block Explorer URL: https://polygonscan.com/
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Source: https://docs.polygon.technology/docs/develop/metamask/config-polygon-on-metamask/
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