Selection Disabler Canceller

selection-disabler-canceller.user.js

// ==UserScript==
// @name     Selection Disabler Canceller
// @version  1.1
// @include  http://*
// @include  https://*
// @grant    none
// ==/UserScript==

(() => {

const GM_log = () => {};//unsafeWindow.console.log;
const REMOVE_STYLE = ["-webkit-touch-callout", "-webkit-user-select", "-khtml-user-select", "-moz-user-select", "-ms-user-select", "user-select"];

const removeStyle = function(rule) {
  var removed = false;
  REMOVE_STYLE.forEach(name => {
    if (typeof rule.style[name] != "undefined" && rule.style[name] != "") {
      rule.style[name] = "";
      removed = true;
    }
  });
  return removed;
};

const cleanDisabler = function(tag) {
  var clean = false;
  if (document.body.onselectstart != null) {
    document.body.onselectstart = null;
    clean = true;
    GM_log("[on" + tag + "] onSelectStart event removed: document.body");
  }
  const disabledElements = Array.from(document.querySelectorAll("*[onselectstart]"));
  for (var i = 0; i < disabledElements.length; i++) {
    try {
    	if (!disabledElements[i].dispatchEvent(new Event("selectstart"))) {
        disabledElements[i].onselectstart = null;
        clean = true;
 				GM_log("[on" + tag + "] onSelectStart event removed: " + disabledElements[i].tagName);
      }
    } catch (e) {
    	disabledElements[i].onselectstart = null;
      clean = true;
 			GM_log("[on" + tag + "] onSelectStart event removed*: " + disabledElements[i].tagName);
    }
  }
  const removedRules = Array.from(document.styleSheets)
      .flatMap(s => {
        try {
          return Array.from(s.rules);
        } catch (e) {
          return null;
        }
      })
      .filter(r => r != null && typeof r.style != "undefined")
      .filter(r => removeStyle(r));
  if (0 < removedRules.length) {
    removedRules.forEach(rule => {
 			GM_log("[on" + tag + "] user-select style removed: " + rule.selectorText);
    });
    clean = true;
  }
  if (clean) {
  	GM_log("[on" + tag + "] Selection disabler cleanup successfuly finished.");
  } else {
  	GM_log("[on" + tag + "] Selection disabler cleanup not applied.");
  }
};

window.addEventListener("load", () => { cleanDisabler("Load") });
cleanDisabler("Init");
})();

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