This is actually the case for ECMAScript (JavaScript). All proposals must first be implemented by some browser vendors at Stage 3: > The proposal has been rec

This is actually the case for ECMAScript (JavaScript). All proposals must first be implemented by some browser vendors at Stage 3: > The proposal has been recommended for implementation. Then, the proposal shall be included in the standard at Stage 4: > Two compatible implementations which pass the Test262 acceptance tests https://tc39.es/process-document/ https://tc39.es/process-document/