Auto Switch Google Account

Auto redirects Google sites to a separate user that is logged in. Useful if you want to set a "default" account without signing out of all accounts.

You will need to install an extension such as Tampermonkey, Greasemonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Userscripts to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install a user script manager extension to install this script.

(I already have a user script manager, let me install it!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(I already have a user style manager, let me install it!)

// ==UserScript==
// @name        Auto Switch Google Account
// @namespace   HowBoutNo
// @description Auto redirects Google sites to a separate user that is logged in. Useful if you want to set a "default" account without signing out of all accounts.
// @match       *://*.google.com/*
// @version     1.2
// @author      HowBoutNo
// @run-at document-start
// @license MIT
// ==/UserScript==

var url = window.location.href;
var uid = 0; // uid is the number corresponding to the account. In URLs it would be the number after /u/

if (url.match("/u/") != null) { // check if site is a Google product (Drive, Mail, etc.)
  if (url.match("/u/" + uid) == null) {
    url = url.replace(/\/u\/[0-9]/, "/u/" + uid)
    window.location.replace(url);
  }
} else if (url.match("authuser=" + uid) == null) { // if not product, site must be Google search which needs to be handled differently
  if (url.match(/\?/) == null) {
    url += "?authuser=" + uid
  } else if (url.match("&authuser=") == null) {
    url += "&authuser=" + uid
  } else {
    url = url.replace(/(authuser=)[0-9]/, "authuser="+uid)
  }
  window.location.replace(url);
}