Sideload Spanish by Martynas Sklizmantas

Sideload Spanish helps you learn Spanish while you browse normally.

It replaces some English words on web pages with Spanish translations, starting with easier vocabulary and unlocking harder words as your progress grows. The goal is lightweight exposure in real context, not flashcards or drills.

Features:
- Progressive vocabulary tiers from beginner to advanced
- Inline word replacement on the pages you already read
- Hover tooltips with the original word and translation
- Click-to-mark-known learning flow
- Struggling-word detection for words you keep seeing but have not learned yet
- Local progress tracking stored in the browser
- Density control for how aggressively words are replaced
- Domain blacklist for sites where you want the extension disabled

Privacy:
- No analytics
- No ad tracking
- No telemetry
- Progress and settings are stored locally by default

The codebase also contains an optional sync capability, but sync settings are currently hidden from the public UI in this submitted version.