This is the skeleton of simple extension cobbled together from stackoverflow that allows you to specify a URL to post data to, and then another URL to redirect to after the successful POST request. It is useful any time that you want to create an extension that will process or scrape data from the current page.
Open the file popup.js and replace the following two URLs with where you'd like to POST to and redirect to:
var postURL = "http://localhost:4567";
var redirectURL = "http://localhost:4567/newurl";
Visit chrome://extensions
in your browser and install this plugin by checking
the developer checkbox, and then loading an unpackaged plugin by pointing at
the directory where you cloned this repo.