Hidden Site Bookmarklet

/* context: https://www.reddit.com/r/operabrowser/comments/ntgbhd/how_to_remove_this/h0t5xp6/ */
javascript: /*HiddenSite*/
(() => {
  let url = "https://en.wikipedia.org", db = document.body, b = window.hidSite, o = window.hidSiteOverlay,
    getEles = () => {
      b = hidSite; o = window.hidSiteOverlay
    },
    hide = () => {
      getEles();
      b.style.cssText = "display:none!important";
      o && o.remove();
      db.classList.remove("sbshow")
    };
  if (o) {
    hide()
  } else if (b) {
    if (b.style.display) {
      b.style.display = "";
      db.classList.add("sbshow")
    } else {
      b.insertAdjacentHTML("beforeend", `<div id="hidSiteOverlay"><div id="hidSitePrompt">
<button id="hide">Hide Hidden Site</button><button id="close">Close Hidden Site</button></div></div>`);
      hidSiteOverlay.focus()
    }
  } else {
    db.insertAdjacentHTML("beforeend", `<div id="hidSite"><style>body.sbshow>*{display:none!important}${
`#hidSite,#hidSite *{all:revert}
#hidSiteFrame{position:fixed;left:0;top:0;border:none;box-sizing:border-box;width:100vw;height:100vh}
#hidSiteOverlay{position:fixed;left:0;top:0;width:100vw;height:100vh;background:rgb(0,0,0,.5);cursor:pointer}
#hidSitePrompt{position:fixed;left:50vw;top:1em;transform:translateX(-50%);border:.2em solid #007;border-radius:.5em;padding:1em;background:#fff;cursor:auto}
body:not(.sbshow):after{position:fixed;right:0;bottom:0;border:1px solid #000;width:.3em;height:.3em;background:#ff0;content:""}
#hidSite button{cursor:pointer}
#hidSite #close{margin-left:3em}`.replace(/([;\}])/g, "!important$1")
}</style><iframe id="hidSiteFrame" referrerpolicy="same-origin"></iframe></div>`);
    hidSiteFrame.src = url;
    hidSite.onclick = ev => {
      getEles();
      switch (ev.target.id) {
        case "hide":
          hide(); break;
        case "close":
          b.remove(); db.classList.remove("sbshow"); removeEventListener("blur", hide); break;
        case "hidSiteOverlay":
          o.remove(); hidSiteFrame.focus()
      }
    };
    addEventListener("blur", hide);
    db.classList.add("sbshow");
    hidSiteFrame.focus()
  }
})()