How do I switch a page to a different domain using a userscript?

Question

I need to replace specific text, in a URL, using Greasemonkey.

For example, if the page is:

http://adf.st/?u=https%3A%2F%2Finstagram.com%2Fp%2F4XOVEaD5Ca%2F

Then the script will use the following URL:

http://adfa.cc/?u=https%3A%2F%2Finstagram.com%2Fp%2F4XOVEaD5Ca%2F

Note: The rest of the text after adf.st/ is not fixed.

Answer 1

This is a standard-ish problem; use the pattern below.

The @match line is set to the old domain, and newDomain is set to the desired domain.

// ==UserScript==
// @name        _Redirect from one domain to another
// @match       *://adf.st/*
// @run-at      document-start
// @grant       none
// ==/UserScript==

var newDomain   = "adfa.cc";
var newURL      = location.protocol + "//"
                + newDomain                 //-- location.host
                + location.pathname
                + location.search
                + location.hash
                ;
/*-- replace() puts the good page in the history instead of the
    bad page.
*/
location.replace (newURL);