featureSwitches.user.js

// ==UserScript==
// @name         Feature Switches
// @namespace    Violentmonkey Scripts
// @version      0.1
// @description  Feature Switches
// @author       adryd
// @match        https://twitter.com/*
// @icon         https://www.google.com/s2/favicons?sz=64&domain=twitter.com
// @grant        none
// @run-at       document-start
// ==/UserScript==

(function() {
    'use strict';
    function initialStatePatcher() {
      let initialState = {}
      Object.defineProperty(window, "__INITIAL_STATE__", {
        set: function set(value) {
          initialState = value
          initialState.featureSwitch.debug = Object.assign({}, value.featureSwitch.user.config);
        },
        get: function get() {
          return initialState
        },
        configurable: true
      })
    }
    const script = document.createElement("script")
    script.text = "(" + initialStatePatcher.toString()+")()"
    document.documentElement.appendChild(script);
})();