Submitted by pauliax, also found by s1m0, shw and 0xRajeev
Hardcoding chainID is error-prone (in case you decide to deploy on a different chain and forget to change this, or if the chain forks, etc):
uint256 public constant override chainId = 1337; // Changes per chain
Recommend better utilization of global variable block.chainid, or you can also retrieve chainID via assembly.
raymogg (Tracer) disputed in a duplicate issue
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