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Preview of PrimeVocab - Dual Subtitle & Spaced Repetition Voc

PrimeVocab - Dual Subtitle & Spaced Repetition Voc by Tolga KASAP

Adds dual subtitles, smart pausing, and a spaced repetition study system to Amazon Prime Video to help you learn vocabulary.

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About this extension
🚀 Transform Your Favorite Movies & Shows Into Language Lessons!

PrimeVocab is the ultimate vocabulary-builder extension for Amazon Prime Video, YouTube, and Netflix. Turn your entertainment time into active learning. By displaying dual subtitles, allowing you to translate and save words with a single click, and reinforcing them using a smart Spaced Repetition System (SRS) and interactive games, PrimeVocab ensures you actually retain the vocabulary you encounter.

Whether you're preparing for IELTS/TOEFL, polishing your conversational English, or picking up a brand-new language, PrimeVocab makes it natural, intuitive, and fun.

🎬 Supported Platforms
* Amazon Prime Video (Full integration, custom controller, IMDb panel hider)
* Netflix (Seamless subtitle overlay and native integration)
* YouTube (Supports original creator captions and experimental ASR)

⭐ Key Features
  1. 🌐 Dual Subtitles & Instant Translation
  2. Watch with two subtitles simultaneously (e.g., Target Language + Native Language).
  3. Smart Translation: Automatically extracts official subtitle tracks if available, or utilizes Google Translate as a fallback.
  4. Interactive Click-to-Save: Hover and click on any word in the subtitles to instantly view its translation, CEFR level (A1-C2), dictionary definitions, and automatically save it to your personal dictionary.
  5. 🧠 Smart Playback Features (Active Learning)
  6. Shadowing Mode: Automatically pause the video at the end of each subtitle line to practice pronunciation. Resume instantly with the Space key.
  7. Smart Shadowing: Intelligent pausing that only interrupts the playback on long or complex sentences, letting you enjoy the show without constant interruptions.
  8. Auto Rewind: Automatically rewind the video by a customizable amount (e.g., 3-5 seconds) whenever you save a word, so you can hear its pronunciation in context again.
  9. Auto Slow-mo: Automatically slows down playback speed (e.g., to 0.8x) when a subtitle contains words you marked as "Hard" or are actively reviewing.
  10. 🃏 Advanced Spaced Repetition (Anki-Style)
  11. A built-in study deck that schedules reviews based on modern memory science.
  12. Rate your recall for each card (Again, Hard, Good, Easy, Learned) to update intervals dynamically.
  13. Set daily limits for new cards and sessions to prevent study burnout.
  14. Monitor your consistency with a 12-week study heatmap, daily streaks (🔥), and progress tracking charts.
  15. 🎮 Mini-Games for Fun Learning
    Tired of flashcards? Reinforce your vocabulary list with 4 interactive mini-games:
  16. Multiple Choice: Find the correct translation out of four options.
  17. Fill in the Blank: Identify the missing word in the context of the sentence from your favorite movie.
  18. Word Scramble: Reorder letters to spell the saved word correctly.
  19. Word Match: Match a grid of target words with their meanings in a race against the clock.
  20. 🗄 Personal Dictionary & Data Control
  21. Detailed Context: Every saved word stores the exact timestamp and movie URL so you can jump back to the exact video frame where you found it.
  22. Organize with Tags: Add tags to words to group them by topic, difficulty, or project.
  23. Complete Privacy & Portability: Export your dictionary as a clean CSV (ready for Anki import) or backup/restore the entire dataset as a JSON file. Fully offline-first design.

⌨ Pro-User Keyboard Shortcuts
Never take your hands off the keyboard while watching:
* Alt + Shift + K: Open or close the sidebar panel.
* Left / Right Arrow: Navigate between words in the active subtitle line.
* Up / Down Arrow: Quick translation/save control.
* Space: Resume playback when paused.

🛡 Privacy & Security First
We value your data privacy. PrimeVocab is completely offline-first. Your vocabulary list, settings, and study progress are stored locally in your browser. Optional cloud sync is handled directly via your personal Google Drive, meaning your data never touches our servers. No trackers, no bloat.
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Permissions and data

Required permissions:

  • Access browser tabs
  • Access your data for sites in the primevideo.com domain
  • Access your data for sites in the amazon.com domain
  • Access your data for sites in the amazon.co.uk domain
  • Access your data for sites in the amazon.de domain
  • Access your data for sites in the youtube.com domain
  • Access your data for sites in the netflix.com domain

Optional permissions:

  • Access your data for sites in the primevideo.com domain
  • Access your data for sites in the amazon.com domain
  • Access your data for sites in the amazon.co.uk domain
  • Access your data for sites in the amazon.de domain
  • Access your data for sites in the pv-cdn.net domain
  • Access your data for sites in the youtube.com domain
  • Access your data for sites in the netflix.com domain
  • Access your data for cf-timedtext.aux.pv-cdn.net
  • Access your data for translate.googleapis.com
  • Access your data for api.dictionaryapi.dev
  • Access your data for api.datamuse.com
  • Access your data for script.google.com
  • Access your data for script.googleusercontent.com

Required data collection, according to the developer:

  • Authentication information
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Version
1.0
Size
229.16 KB
Last updated
3 days ago (Jun 27, 2026)
Related Categories
  • Language Support
  • Games & Entertainment
License
All Rights Reserved
Version History
  • See all versions
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