cursed.js

function cursedPromise() {
    return new Promise(resolve => {
        if (Math.random() > 0.5) resolve();
    });
}

async function main() {
    await cursedPromise();
    console.log("after await");
    return "ok";
}

// Half the time this will print:
//
//   after await
//   result: ok
//   finally!
//
// and the other half the time NOTHING AT ALL
main()
    .then(
        result => console.error("result:", result),
        error => console.error("error:", error),
    )
    .finally(() => console.log("finally!"));