Build a custom Chrome extension with Manus

A specific description gets you a first version close to what you want.

1. 1Go to manus.im/app and sign in.
2. 2In the mode menu at the top, pick Manus 2.0 on Pro, or Manus 2.0 Lite on Free.
3. 3Paste the prompt below and fill in the brackets: what it does, where results show and which sites it runs on.
4. 4Send the message.

Build a Chrome extension (Manifest V3) that [WHAT IT DOES, E.G. "finds every email address on the current page"].

Show the results in a [POPUP / SIDE PANEL] with [CONTROLS, E.G. "a sort button and a Copy all button"].
Run it on [ALL SITES / ONE SITE, E.G. EXAMPLE.COM], only when I click the extension icon.
Use the fewest permissions possible, such as activeTab.
Style: [MINIMAL / MODERN].

Test it, then put every file in one .zip and attach it, with short steps to install it in Chrome.

You should see Manus planning the build and creating files such as manifest.json.

The activeTab permission only lets the extension read the tab you're on after you click it. Chrome shows no install warning for it.

Manus writes and checks the code in its own cloud computer, so you only handle the finished files.

1. 1Wait for Manus to finish. It writes the manifest, the scripts and the popup or panel files.
2. 2Read its install notes, then download the .zip from its last reply.
3. 3Unzip it into a folder you'll keep, such as one called extensions in your Documents folder.

You should see a folder with a manifest.json file in it, next to the extension's other files.

In Manus Studio, the desktop app, you can turn on Work locally and pick a folder. Manus then works with the files on your computer.

Developer mode lets Chrome run an extension straight from a folder on your computer.

1. 1Open a new tab and go to chrome://extensions.
2. 2Turn on the Developer mode toggle.
3. 3Click Load unpacked and select the folder that holds manifest.json.
4. 4Click the Extensions puzzle button in the toolbar and pin your extension.

You should see your extension's card on the Extensions page, and its icon in the toolbar.

An unpacked extension can read the pages it runs on. Load only code you asked for, and remove it from this page when you're done with it.

A quick test on a live page shows what works before you ask for changes.

1. 1Open a page the extension should work on, such as a contact page for an email finder.
2. 2Click the extension's icon in the toolbar.
3. 3If nothing happens, go back to chrome://extensions and click Errors on its card.

You should see the popup or side panel showing results from the page you're on.

Small changes, one at a time, are easier for Manus to get right and for you to test.

1. 1In the same Manus task, ask for one change, such as "Widen the popup" or "Add a button that copies everything."
2. 2Download the new .zip and replace the files in your extension folder.
3. 3On chrome://extensions, click the refresh icon on your extension's card.
4. 4Reload the web page, then test the change.

You should see the change working, with no new errors on the extension's card.

Chrome's docs say changes to the manifest or service worker need the refresh icon. Changes to scripts that run on pages also need a page reload.