Headline Sentiment Highlighter (Prototype)

A Chrome Manifest V3 extension that finds likely headlines on news sites (NYTimes, WaPo, BBC, CNN) and overlays a green→red gradient based on a simple sentiment score.

Install (Developer Mode)

1. Download and unzip the archive.
2. Open Chrome → chrome://extensions.
3. Toggle Developer mode (top-right).
4. Click Load unpacked and select the folder headline-sentiment-highlighter.
5. Navigate to nytimes.com (or another supported site) and you should see colored headlines and a floating toggle.

How it works

• Runs a content script that:
  • Queries for headline-like elements (h1/h2/h3, roles, common headline classes).
  • Scores the text with a tiny lexicon-based sentiment (no network, no API key).
  • Applies a CSS linear-gradient: green for positive, red for negative. Opacity scales with magnitude.
  • Adds a small floating toggle to enable/disable coloring.
  • Watches the page for new content via MutationObserver.

This is a lightweight prototype intended to prove out the interaction. For richer accuracy, swap the tiny lexicon for a fuller model (e.g., AFINN/Valence shifters or a cloud NLP API).

Customize

• Targets: Edit content.js → getCandidateHeadlines() to add/removes selectors tailored to specific sites.
• Color/Intensity: Tweak colorForScore().
• Dictionary: Expand the POSITIVE / NEGATIVE maps with more words/weights.

Notes

• This prototype avoids external dependencies to keep the packaging simple.
• Headline markup changes frequently on news sites; updating selectors may be needed.