You can also buy without connecting: send ETH to the contract from any wallet.iThe contract mints to whoever sent the ETH, so a plain transfer from any wallet works, including hardware. No approvals, no router, no connection to this site.

Two caveats. A plain send has no slippage bound, which is safe here only because there is no pool to sandwich. And selling always needs a connected wallet, because it is a contract call rather than a transfer.