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Preview of PrimeVocab - Dual Subtitle & Spaced Repetition Voc

PrimeVocab - Dual Subtitle & Spaced Repetition Voc by PrimeVocab

Adds dual subtitle support, smart auto-pause, and spaced repetition (SRS) vocabulary learning on Amazon Prime Video, Netflix, and YouTube.

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Available on Firefox for Android™Available on Firefox for Android™
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About this extension
About This Extension
🚀 Turn Your Favorite Shows and Movies Into a Language Lesson!

PrimeVocab is the most advanced vocabulary-builder extension designed for Amazon Prime Video, YouTube, and Netflix. Turn your entertainment time into an active learning process. With dual subtitles, one-click word translation and saving, reinforced by a smart Spaced Repetition System (SRS), an achievements/badge system, and fun mini-games, PrimeVocab helps you actually retain the words you encounter.

Whether you're preparing for IELTS/TOEFL, improving your everyday conversational English, or learning 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 layer with native integration)
YouTube (Original channel captions plus experimental auto-generated (ASR) caption support)
⭐ Key Features

🌐 Dual Subtitles & Instant Translation
Watch videos with two subtitles at once (e.g. Target Language + Native Language).
Smart Translation: Pulls official subtitle tracks when available, falls back to Google Translate otherwise.
Click & Save: Hover and click any word in the subtitles to instantly see its translation, CEFR level (A1–C2), dictionary definitions, and save it to your personal dictionary.
Idiom, Phrasal Verb & Collocation Highlighting: Common patterns are auto-detected in subtitles; multi-word collocations you've saved to your dictionary are also recognized as a single unit and highlighted in a distinct color.
🧠 Smart Playback Features (Active Learning)
Shadowing Mode: Automatically pauses the video at the end of every subtitle line so you can practice pronunciation. Press Space to resume instantly.
Smart Shadowing: Doesn't pause on every sentence — only pauses on sentences containing C1/C2-level vocabulary, words you've marked as "hard," idioms, or phrasal verbs, so you can practice without interrupting the movie's flow.
Auto-Rewind: When you save a word, automatically rewinds the video by a duration you choose (e.g. 3–5 seconds) so you can re-hear the word's pronunciation in context.
Auto Slow-Motion: Automatically slows playback speed (e.g. to 0.8x) when words you've marked "Hard" or are actively studying appear in the subtitles.
🏆 Achievements & Badges
A tiered badge system that reinforces learning Phrasal Verbs, Idioms, and Collocations (Verb Explorer, Phrasal Guru, Idiom Hunter, Idiom Sage, Collocation Seeker, Collocation Architect, and more).
Track your progress via the level and badges screen to stay motivated.
🃏 Advanced Spaced Repetition (Anki-style)
An integrated deck that builds a study schedule based on modern memory science.
Rate cards based on recall (Again, Hard, Good, Easy, Learned) and dynamically update review intervals.
Set daily new-card and session limits to prevent mental fatigue.
Track your 12-week study heatmap, daily streaks (🔥), and progress charts.
🎮 Fun Mini-Games Tired of classic flashcards? Reinforce your dictionary words with 6 different mini-games, and optionally focus your practice on a specific category (e.g. Collocations Only):
Multiple Choice: Pick the correct translation from four options.
Fill in the Blank: Find the missing word in a sentence from the show you were watching.
Word Builder: Unscramble the letters to form the correct word.
Word Match: Match the words with their meanings.
Dictation: Type the word you hear correctly.
Memory Cards: Match words with their translations by flipping cards.
🗄 Personal Dictionary & Data Control
Rich Context: Every saved word stores the exact timestamp and video link, so you can jump straight back to the scene where you learned it.
Organize with Tags: Add tags to group words by topic, difficulty, or personal projects.
Full Privacy and Portability: Export your dictionary as a clean CSV ready for Anki import, or back up/restore your entire dataset as a JSON file. Fully local, offline-first design.
⌨ Power-User Shortcuts Keep your hands on 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 and word-saving controls.
Space: Resume a paused video.
🛡 Privacy & Security First We take your data privacy seriously. PrimeVocab runs entirely locally (offline-first). Your dictionary, settings, and progress are stored locally in your browser. Optional cloud sync goes through your own personal Google account — your data is never sold or transferred to third-party servers. No ads, no trackers.
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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
  • Access your data for prime-vocab-mobile.vercel.app

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 sites in the googleapis.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 accounts.google.com
  • Access your data for script.google.com
  • Access your data for script.googleusercontent.com
  • Access your data for prime-vocab-mobile.vercel.app
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Version
1.3.3
Size
431.25 KB
Last updated
2 days ago (Aug 30, 2026)
Related Categories
  • Language Support
  • Games & Entertainment
License
All Rights Reserved
Version History
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