HighlightVault

Persistent web highlighter — 100% local, zero accounts, zero cloud.

HighlightVault is a Chrome extension that lets you highlight text on any web page with multiple colors. Your highlights persist across visits and are stored entirely on your device using chrome.storage.local.

Features

• Multi-color highlighting — Select text and pick from 4 colors (yellow, purple, green, blue)
• Persistent highlights — Highlights reappear automatically when you revisit a page
• Organized popup — Browse all your highlights grouped by website with search
• One-click navigation — Click any highlight in the popup to jump back to the page
• Markdown export — Export all highlights as formatted Markdown to your clipboard
• Delete highlights — Click any existing highlight to remove it
• Badge counter — See how many highlights are on the current page at a glance
• Enable/Disable toggle — Turn highlighting on or off from the popup
• Zero dependencies — No accounts, no cloud, no tracking. Everything stays on your device.

Installation

1. Clone or download this repository
2. Open Chrome and navigate to chrome://extensions/
3. Enable Developer mode (toggle in the top right)
4. Click Load unpacked and select the HighlightVault folder
5. Pin the extension from the puzzle icon in the toolbar

Usage

1. Highlight text — Select any text on a web page. A tooltip with 4 color dots appears above the selection.
2. Pick a color — Click a color dot to apply the highlight.
3. Remove a highlight — Click on an existing highlight, then click the × button.
4. Browse highlights — Click the HighlightVault icon in the toolbar to see all highlights organized by site.
5. Search — Use the search bar in the popup to filter highlights by text or domain.
6. Export — Click "Export as Markdown" to copy all highlights to your clipboard.

Tech Stack

• Manifest V3 Chrome Extension
• Vanilla JavaScript (no frameworks, no build step)
• chrome.storage.local for persistence
• CSS animations for smooth UI

Project Structure

HighlightVault/
├── manifest.json       Manifest V3 configuration
├── content.js          Content script — selection detection, highlighting, restoration
├── content.css         Tooltip and highlight styles
├── popup.html          Extension popup markup
├── popup.js            Popup logic — listing, search, export
├── popup.css           Popup styles
├── background.js       Service worker — badge updates, message routing
├── icons/
│   ├── icon16.png
│   ├── icon48.png
│   └── icon128.png
└── README.md

License

MIT