Last updated: June 2026

<aside> 🛡️ Sanctum is a focus-support browser extension for YouTube. Its purpose is to help users notice and interrupt repetitive browsing patterns such as feed checking, Shorts scrolling, refresh loops, and impulsive video selection.

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1. Data processed locally

Sanctum’s core detection and decision logic run in the user’s browser.

Sanctum may store the following data locally in the user’s browser:

• User settings such as language preference, focus mode, feedback position, excluded domains, and opt-in preference
• Local feedback records
• Local media cache
• Recent playback history
• Local extension state needed for focus-support features

This local data is used only to provide Sanctum’s focus-support features.

2. Optional improvement data

Users may optionally submit free-text feedback. This feedback is used only to improve Sanctum and is not sold, shared for advertising, or used for creditworthiness decisions. Sanctum does not send improvement data unless the user explicitly opts in.

If the user enables improvement data sharing, Sanctum may send minimal non-identifying summary events for rule improvement. These events may include:

• Rule ID
• Rule category
• Intervention type
• User action result
• Feedback label
• Time bucket values