Capture any page or highlighted text to your Second Brain with one click or a keyboard shortcut — without leaving the tab.
This extension requires a deployed Second Brain Cloudflare Worker. If you haven't set that up yet, start there first:
github.com/rahilp/second-brain-cloudflare
The Worker is free to deploy (Cloudflare free tier), takes about 2 minutes via the one-click deploy button, and gives you a Worker URL + auth token you'll need to connect the extension.
- Capture the current page — saves the title and URL to your second brain
- Capture highlighted text — select any text on a page before clicking capture; the excerpt is saved alongside the title and URL
- Add a note — type context or
#hashtagsin the popup before saving; hashtags are automatically extracted as tags - Quick capture — keyboard shortcut saves the page instantly without opening any popup, with a toast confirmation
No app store required. Load the extension directly from source in about 60 seconds.
- Clone this repo:
git clone https://github.com/rahilp/second-brain-browser-extension.git
- Go to
chrome://extensions - Enable Developer mode (toggle in the top-right corner)
- Click Load unpacked and select the cloned folder
- The Second Brain icon appears in your toolbar — pin it for easy access
Same steps, but go to edge://extensions in step 2 and enable Developer mode from the left sidebar.
When a new version is released, pull the latest changes and reload the extension:
git pullThen go to chrome://extensions and click the reload icon on the Second Brain card.
On first install, the extension opens a setup page automatically.
- Enter your Worker URL (e.g.
https://your-worker.workers.dev) - Enter your Auth Token (the
AUTH_TOKENsecret you set when deploying) - Click Connect — the extension verifies the connection and saves your credentials
To update your settings later, click the gear icon in the popup.
Click the Second Brain icon in your toolbar (or press Alt+Shift+B).
| Element | What it does |
|---|---|
| Page info | Shows the title and URL that will be captured |
| Selection badge | Appears when text is highlighted — the excerpt will be included |
| Note field | Optional context to save with the capture. Use #hashtags to tag |
| Capture button | Sends to your Second Brain |
| Shortcut | Action |
|---|---|
Alt+Shift+B (Mac: ⌥ Shift B) |
Open the popup |
Alt+Shift+S (Mac: ⌥ Shift S) |
Quick capture — saves instantly, no popup |
Quick capture shows a toast notification in the top-right corner of the page confirming the result. You can customise both shortcuts at chrome://extensions/shortcuts.
| Result | Meaning |
|---|---|
| Captured | Saved successfully |
| Already in your brain | Near-duplicate detected — not saved again |
| Merged / Updated | Similar existing memory was updated instead |
The extension builds the content string sent to /capture:
Page title
https://page-url.com
Highlighted: "selected text if any"
Your note with #hashtags
Hashtags in the note are extracted as tags by the Worker. The source field is set to "extension" so you can filter by it in your second brain.
| Permission | Why |
|---|---|
activeTab |
Read the current tab's title and URL |
scripting |
Get selected text from the page; inject toast notifications |
storage |
Save your Worker URL and auth token locally |
host_permissions: <all_urls> |
Make requests to your self-hosted Worker URL (which can be any domain) |
Credentials are stored in chrome.storage.sync — they never leave your browser except in requests to your own Worker.
manifest.json — Extension manifest (MV3)
background.js — Service worker: handles quick-capture command + toast injection
popup.html/js/css — Capture popup UI
setup.html/js/css — First-run setup and settings page
icons/ — Extension icons
- second-brain-cloudflare — the Cloudflare Worker this extension connects to
- second-brain-obsidian-plugin — Obsidian plugin
- second-brain-cli — CLI tool
MIT