Installation

The extension is not published to the Chrome Web Store, so it has to be built once and loaded unpacked.

Requirements

• A Chromium-based browser with Manifest V3 support: Chrome, Edge, Brave, Vivaldi or Opera.
• Node.js 20 or newer and npm, to run the webpack build.

Build and load

1. Clone and install dependencies

   git clone https://github.com/rennerdo30/mail-thread-export.git
   cd mail-thread-export
   npm install

2. Build the extension

   npm run build

   This runs webpack in production mode. It bundles src/content/scanner.js (and everything it imports, including jspdf and html2canvas) into a single dist/content.js, and copies the manifest, the injected stylesheet, the icons, the popup and the background script into dist/.

3. Open the extensions page

   Navigate to chrome://extensions (edge://extensions on Edge, brave://extensions on Brave).

4. Enable Developer mode

   The toggle sits in the top-right corner of the extensions page.

5. Load the dist/ directory

   Click Load unpacked and select the dist/ folder — not the repository root. The manifest lives in dist/manifest.json after the build.

6. Reload any open Gmail tab

   Content scripts are only injected on page load, so a Gmail tab that was already open before installing will not have the Export button until you reload it.

`dist/` is gitignored

A fresh clone contains no build output. npm run build is mandatory before the first load, and after every change to anything in src/.

Verify it works

1. Open https://mail.google.com/ and open any conversation.
2. An Export button should appear immediately to the right of the subject heading.
3. The browser console should contain Mail Thread Export: content script loaded.

If the button is missing, see Development.

Rebuilding while you work

npm run watch

Webpack stays running and rebuilds dist/ on every save. You still have to press the reload icon on the extension card in chrome://extensions and reload the Gmail tab, because content scripts are not hot-reloaded.

Uninstalling

Remove the extension from chrome://extensions. Nothing is stored outside the extension directory — there are no preferences, no cached data and no server-side state to clean up.