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Preview of Marklet

Marklet by Reza Jelodar

Highlight and annotate web pages with marker-style overlays and freehand drawings.

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About this extension
Marklet: The Professional-Grade Web Annotation Engine

Transform the web into your personal, persistent notebook. Marklet is a high-performance, open-source browser extension designed for researchers, developers, and students who require more than just a simple highlighter.

Most annotation tools break when a website updates its layout or when you refresh the page. Marklet is different. Engineered with precision and stability in mind, it uses advanced DOM-traversal and coordinate mapping to ensure your notes stay exactly where you put
them.

Key Features:
  1. Precision Highlighting & Deep Linking
  2. Robust Persistence: Highlights are anchored using high-fidelity range analysis, allowing them to survive page shifts and content updates.
  3. Smart Fragment Linking: Generate robust "Scroll-to-Text" URLs (#:~:text=) that include prefix and suffix context. Share a link that takes you directly to a specific highlight, even if that text appears multiple times on the page.
  4. Instant Management: Hover over any highlight to change colors, copy the direct link, or delete it instantly.
  5. Infinite Whiteboard Mode
  6. Dual-Layer Architecture: Draw on a high-performance Canvas layer for a lag-free experience, then watch it seamlessly transition to a persistent SVG layer that scrolls naturally with the page elements.
  7. Smart Shapes & Tools: Beyond freehand sketching, use dedicated tools for perfect Rectangles, Circles, Arrows, and integrated Text annotations.
  8. Typography Matching: Text notes automatically adopt the host site’s font-family, weight, and smoothing for a native look and feel.
  9. Advanced Annotation Dashboard
  10. Local Knowledge Base: A modernized, card-based dashboard lets you browse, search, and filter every annotation you’ve ever made.
  11. Quick Snippet Actions: Manage your research without opening every page—copy text snippets, jump to specific highlights, or delete old entries directly from the settings.
  12. Engineered for Performance
  13. Zero Layout Lag: Uses layout-aware WeakMap caching to prevent expensive browser reflows, ensuring the extension stays fast even on massive, complex documentation pages.
  14. Adaptive Scheduling: A sophisticated background scheduler manages data persistence with minimal impact on your browser’s main thread.
  15. Shadow DOM Isolation: Every UI element is fully encapsulated, ensuring Marklet never conflicts with or breaks the styling of the websites you visit.

Why Choose Marklet?
  • 100% Privacy-First: Your data is yours. Marklet stores everything locally using IndexedDB and Chrome's storage API. No accounts, no servers, and zero data transmission.
  • Unlimited Storage: Leverage the full capacity of your local machine. Store thousands of highlights and complex drawings without hitting artificial limits.
  • Open Source & Transparent: Licensed under GNU GPL 3. Marklet is built with vanilla JavaScript—no external trackers, no bloated frameworks, and no hidden dependencies.
  • Content Security Policy (CSP) Friendly: Designed to operate safely within the most restrictive security environments, including enterprise and financial applications.

Stop losing your research to page refreshes and layout changes. Install Marklet today and build a web-wide knowledge base that lasts.
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Permissions and data

Required permissions:

  • Access browser activity during navigation
  • Access your data for all websites

Optional permissions:

  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
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Version
1.2.5
Size
162.78 KB
Last updated
5 days ago (Jun 13, 2026)
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License
MIT License
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