Add parameters to the URL (redirect) via a Greasemonkey/Tampermonkey/Userscript

Question

I\'d like to write a Greasemonkey/userscript that automatically adds .compact to URLs starting with https://pay.reddit.com/ so It automatically redirects me to

Answer 1

The example script you showed is using a regex to manipulate the window's location:

replace(/^https?:\/\/(www\.)?twitter.com/, 'https://mobile.twitter.com');

Unsurprisingly, this replaces https://www.twitter.com and http://twitter.com etc. with https://mobile.twitter.com.

Your situation is slightly different, because you want to append a string to your url if it matches some regex. Try:

var url = window.location.href;
var redditPattern = /^https:\/\/pay.reddit.com\/.*/;
// Edit: To prevent multiple redirects:
var compactPattern = /\.compact/;
if (redditPattern.test(url)
    && !compactPattern.test(url)) {
    window.location.href = url + '.compact';
}

See: http://jsfiddle.net/RichardTowers/4VjdZ/3 for test case.