/*jslint browser: true, devel: true, indent: 2 */

var CFFVK;

CFFVK = CFFVK || (function () {
  'use strict';

  var settings;

  function processFeedItem(elem, setting, newClassName) {
    var parent = elem.parentNode;

    while (parent !== CFFVK.feed) {
      if (parent.className.indexOf('feed_row') > -1) {
        if (setting === 'checked') {
          if (parent.className.indexOf(newClassName) === -1) {
            parent.className += newClassName;
          }
          return;
        }
        newClassName = new RegExp(newClassName, 'g');
        parent.className = parent.className.replace(newClassName, '');
        return;
      }
      parent = parent.parentNode;
    }
  }

  function find(className, setting) {
    var els = CFFVK.feed.getElementsByClassName(className),
      l = els.length,
      newClassName = 'cffvk-' + className,
      i,
      el;

    for (i = 0; i < l; i += 1) {
      el = els[i];
      if (!(newClassName === 'cffvk-wall_post_source_default' &&
          el.href.indexOf('app3698024') > -1)) {
        processFeedItem(el, setting, ' ' + newClassName);
      }
    }
  }

  return {
    clean: function clean(receivedSettings) {
      var els = CFFVK.feed.getElementsByTagName('a'),
        l = els.length,
        i,
        el;

      if (receivedSettings) {
        settings = receivedSettings;
      }

      for (i = 0; i < l; i += 1) {
        el = els[i];
        if (/sprashivai\.ru|spring\.me|nekto\.me|ask\.fm/.test(el.href)) {
          processFeedItem(el, settings.links, ' cffvk-links');
        }
      }

      find('group_share', settings.group_share);
      find('event_share', settings.event_share);
      find('wall_post_source_default', settings.apps);
      find('wall_post_more', settings.wall_post_more);
      find('post_like_icon no_likes', settings.likes);
      find('reply_link', settings.comments);

      console.log('CFFVK: your feed has been cleaned');
    },

    observer: new window.MutationObserver(function (mutations) {
      if (mutations[0].addedNodes.length > 0) {
        CFFVK.clean();
        console.log('       by the MutationObserver');
      }
    })
  };
}());

CFFVK.feed = document.getElementById('feed_rows');

CFFVK.observer.observe(CFFVK.feed, {
  childList: true
});

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@@ -2202,9 +2202,9 @@
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