How do I change the Optimism endpoint on MetaMask?

Here are the steps to change the Optimism endpoint on MetaMask, for example because you'd rather use an endpoint from a node provider:

1. Open MetaMask.
2. Change the network to something other than Optimistic Ethereum (for example, Ethereum Mainnet).
   
   
   
   
3. Remove the Optimistic Ethereum network (and click Delete to confirm).
   
   
   
   
4. Click the circle icon at the top right and select Settings.
   
   
   
   
5. Click Networks and then Add Network.
   
   
6. Enter the network parameters:
   
   

   Network Name	Optimism
   New RPC URL	The new RPC URL
   Chain ID	10
   Currency Symbol	ETH
   Block Explorer URL	https://optimistic.etherscan.io

    

7. Click Save.
8. Congratulations, you can now use Optimism through the new endpoint.