OTOTOY - No Volume Playback | Ensure that you don't get ear-raped when you open an album page and the trial song start blasting.

ototoy-zero-volume.user.js

// ==UserScript==
// @name        OTOTOY - No Volume Playback
// @namespace   n4o-ototoy-script
// @match       https://ototoy.jp/_/default/p/*
// @grant       none
// @version     1.0
// @author      N4O
// @description Ensure that you don't get ear-raped when you open an album page and the trial song start blasting.
// ==/UserScript==

(() => {
  // XXX: You can change this timeout, I'm too lazy to use MutationObserver.
  // Default to 10s
  const timeout = 10 * 1000;

  let timeoutHandler;
  let intervalHandler;
  
  function log(...message) {
    console.log("[OTOTOY Volume]", ...message);
  }

  function dispatchVolume(audioJsWrap) {
    const volumeInput = audioJsWrap.querySelector("div.volume > input");
    if (volumeInput) {
      log("dispatch 0% volume to:", volumeInput);
      volumeInput.value = "0";
      // Dispatch input event since ototoy are doing something with it.
      volumeInput.dispatchEvent(new Event("input", { bubbles: true }))
    }
  }

  function main() {
    log("dispatcher ready!");

    const audioJs = document.querySelector("#audiojs_wrapper0");
    if (audioJs) {
      log("initial ready get!");
      dispatchVolume(audioJs);
      return;
    }

    intervalHandler = setInterval(() => {
      const audioJs = document.querySelector("#audiojs_wrapper0");
      if (audioJs) {
        log("get audioJs in interval:", audioJs);
        dispatchVolume(audioJs);
        clearInterval(intervalHandler);
        if (timeoutHandler) {
          clearTimeout(timeoutHandler);
        }
      }
    }, 500);

    timeoutHandler = setTimeout(() => {
      log("timeout!");
      if (intervalHandler) {
        clearInterval(intervalHandler);
      }
    }, timeout);
  }

  if (document.readyState !== "loading") {
    main();
  } else {
    document.addEventListener("DOMContentLoaded", main);
  }
})();