Sage - StopDoomScrolling 作者： Rachit Singh

Sage is a lightweight, privacy-first browser extension designed to kill doomscrolling without breaking the internet.

Unlike traditional website blockers that treat the internet as black-and-white (completely blocking YouTube or Instagram), FocusGuard uses an Intentional Usage Model. It allows you to use social platforms for real, productive tasks while surgically removing the algorithmic feeds designed to steal your attention.

Everything runs locally, is built with pure Vanilla JavaScript (zero heavy frameworks), and features a premium dark glassmorphism aesthetic.



Sage isn't just a basic timer or blocker—it actively understands why you are on the internet and adapts to your workflow.


Sage understands the difference between intentional browsing and mindless scrolling.
* On YouTube: If you search for a specific tutorial or click a direct link, FocusGuard lets you watch the video but surgically removes the sidebar recommendations, autoplay videos, and end-screen suggestions. If you visit the homepage, it hides the algorithmic grid but leaves the search bar perfectly usable.
* On Instagram: You can still check direct messages, search for specific profiles, or view stories. But if you click on the Reels tab or the Home feed, the algorithmic content is instantly blocked and replaced with a Focus Card.


You don't always have to tell FocusGuard what you are doing—it figures it out. By analyzing a short-lived rolling buffer of your recent tabs, it runs a 3-tier local inference algorithm to figure out your current task:
1. Search Extraction: It reads your active search queries on Google, DuckDuckGo, or YouTube (e.g., extracting "how to center a div").
2. Title Analysis: It parses and cleans the titles of the articles or docs you are reading.
3. Domain Mapping: It maps specific domains to productivity contexts (e.g., github.com = Coding, figma.com = Designing).

When you get distracted and open a blocked feed, FocusGuard doesn't just say "Blocked." It actively reminds you of what you were just doing: "⚠ Don't get distracted. Keep working on: how to center a div."


FocusGuard isn't a tyrant. If you open your browser on a Saturday morning and immediately go to Instagram (with no recent work tabs open and no active tasks on your to-do list), the extension realizes you aren't trying to work.

Instead of aggressively blocking you, it gently prompts: "Do you want to chill today?" If you click yes, it gets out of your way.


Taking a break is allowed, but it requires conscious effort. To bypass the block, you must complete a randomized, dynamically generated CAPTCHA string. This minor friction is enough to break the muscle-memory loop of opening a new tab and clicking YouTube.

• Blazing Fast SPA Detection: Modern sites like YouTube and Instagram are Single Page Applications (SPAs). FocusGuard uses highly optimized <title> tag MutationObservers combined with the background webNavigation API to detect page changes instantly without slowing down your scrolling performance.
• Shadow DOM Isolation: All focus cards and overlays are injected using closed Shadow DOMs. This ensures that the host website's CSS can never break the extension's beautiful UI.
• Zero Bloat: Built completely without React, Vue, or Webpack. The entire extension is powered by modular, plain JavaScript, making its memory footprint practically invisible.
• Manifest V3: Fully compliant with the latest security and performance standards for both Chrome and Firefox.