Here are some things to keep in mind when using a Ledger hardware wallet with MetaMask to connect to the Celo network.
When using MetaMask with a Ledger, users should open the Ethereum app on their Ledger hardware device, not the Celo app.
(Users using a Celo-specific wallet with the Ledger should still use the Celo app though)
When recovering Celo sent to an Eth address, use Metamask with the Ethereum app on the Ledger device.
When recovering Eth sent to a Celo address, use the Celo app on the Ledger device with any Celo wallet.