Copy this code to the console and run it:

(() => {
  let log = document.getElementById('log');
  log.innerText += '\nTesting libsodium';
  window.sodium.ready.then(() => {
    log.innerText += '\nlibsodium ready';
    let now = performance.now();
    let result = window.sodium.crypto_pwhash(32, window.sodium.from_string('test'), new Uint8Array(16), window.sodium.crypto_pwhash_OPSLIMIT_INTERACTIVE, window.sodium.crypto_pwhash_MEMLIMIT_INTERACTIVE, window.sodium.crypto_pwhash_ALG_DEFAULT);
    log.innerText += `\nTook ${performance.now()-now}ms. This number should be 141: ${result[0]}. Now try refreshing and running in the console again`;
  });
})();