MR Links Extension

A lightweight browser extension that makes reading Marginal Revolution's assorted links posts easier by showing the referenced link above each comment.

Installation

Option 1: Install from Chrome Web Store (Recommended)

1. Visit the MR Links extension on Chrome Web Store
2. Click "Add to Chrome"
3. Confirm the permission prompt
4. Done! The extension is now active on all Marginal Revolution assorted links posts

Option 2: Clone & Run Your Own Fork

If you want to modify the extension or run a custom version:

1. Clone the repository:

   git clone https://github.com/YOUR_USERNAME/mr-links-all.git
   cd mr-links-all/mr-links

2. Open Chrome and go to chrome://extensions/

3. Enable "Developer mode" (toggle in top right)

4. Click "Load unpacked"

5. Select the mr-links/ directory from your cloned repo

6. The extension is now loaded. Any changes to content.js or content.css will take effect after a page refresh.

Development Notes

• Manifest V3 requires reloading the extension after code changes
• To reload: Go to chrome://extensions/, find "MR Links", and click the refresh icon
• Test on: https://marginalrevolution.com/marginalrevolution/ (any assorted links post)

How It Works

When you visit a Marginal Revolution "assorted links" post:

1. The extension parses the numbered links from the post (1-10 links)
2. It scans each comment for references: #X, X., or X)
3. For each reference, it injects a small banner above the comment showing the link's title and URL
4. Click the banner to open the link in a new tab

Files

• manifest.json — Extension configuration (Manifest V3)
• content.js — Main logic: parses links, finds references, injects banners
• content.css — Styles for the injected banners
• icons/ — Extension icons (16x48x128 px)

Testing

1. Navigate to any Marginal Revolution "Assorted Links" post (e.g., https://marginalrevolution.com/marginalrevolution/2026/04/tuesday-assorted-links-565.html)

2. Scroll to the comments section

3. Look for comments that reference a link number, such as:

   • #2 – This is interesting...
   • 4. Why leave out...
   • Following up on 7)

4. You should see a blue banner above each comment showing the title and URL of the referenced link

5. Click the banner to open the link in a new tab

Design

• URL guard: Only activates on assorted-links posts (not every MR page)
• Link parsing: Handles both <ol> lists and numbered paragraphs
• Reference detection: Regex-based, finds #X, X., X) patterns
• Non-intrusive: Light styling, inserted between author line and comment text
• Performance: Vanilla JS, no dependencies, minimal DOM overhead

Privacy

MR Links does not collect, store, or transmit any user data. The extension only operates on marginalrevolution.com and performs all processing locally in your browser.