How to fill out a textfield within a form on a webpage from a chrome extension?

Question

So far I have got an extension that lists out the webpage the user is on and a button. The button should, when clicked, fill in the textfield with \"testing123\".

On th

Answer 1

You can't access the webpage directly from popup. You should use content scripts to do this. Content scripts run in the context of the webpage.

Add this to your manifest :

"content_scripts": [
        {
            "matches": [
                "http://www.example.com/*"
            ],
            "js": [
                "jquery.js",
                "myscript.js"
            ]
        },

myscript.js :

$("#body").val("testing123");

document.getElementById('body').value = 'testing123';