PageHalo

Add colored borders to pages based on their domain. Visually distinguish your environments at a glance.

PageHalo — Color borders by domain Instantly tell which environment you're looking at. PageHalo draws a colored border around the browser viewport based on the domain you're visiting. Perfect for distinguishing production from staging, or keeping track of multiple services at a glance. FEATURES - Domain-based rules: Assign a color to any domain (e.g., github.com → red, localhost → green). - Per-site border thickness: Each rule has its own thickness slider (1–12px) so you can make important environments stand out more. - Non-intrusive border: A colored inset border that doesn't affect page layout or block clicks. - "This page" button: One click grabs the current tab's domain — no typing needed. - Inline editing: Click any rule's color dot, domain text, or thickness slider to edit it on the spot. - Import / Export: Copy your config as JSON and paste it into another browser or share it with your team. - Live updates: Border appears and disappears instantly as you add, edit, or remove rules — no page reload required. - Synced across devices: Rules are stored in Chrome Sync, so they follow you everywhere you're signed in. HOW IT WORKS 1. Click the PageHalo icon in the toolbar. 2. Type a domain (or press "This page") and pick a color. 3. Adjust the thickness slider to your liking. 4. Hit + to save. Done — every page on that domain now has a colored border. USE CASES - Dev environments: Green for localhost, yellow for staging, red for production. Use a thicker border for prod so you never miss it. - Client projects: Different color per client domain so you always know whose site you're on. - Focus zones: Color-code the sites you use for work vs. personal browsing. PRIVACY PageHalo does not collect, transmit, or store any personal data. All rules are saved locally in Chrome Sync storage and never leave your browser. No analytics, no tracking, no network requests. See our full privacy policy for details.