By: Darius
Check if a domain has HSTS enabled: max-age, includeSubDomains, and preload status.
This add-on was removed from Firefox Add-ons Store on 2026-03-19
User Growth & Download Statistics
Manifest V2 Add-on
- By:
- Darius
- Daily users:
- -
- Version:
- 1.0.0 Last updated: 2026-03-16
- Version code:
- 6181042
- Creation date:
- 2026-03-13
- Risk:
- Very low risk impact High risk likelihood
- Size:
- 14.68KB
- Source:
- Firefox Add-ons Store
- Data ingested on:
- 2026-03-19
- Compare stats and ranking:
- Security Header Checker vs Strict Transport Checker
- Security Header Checker vs HSTS Checker
- Security Header Checker vs HTTPS+ Checker
Contact the developer
Chrome-Stats does not own this Firefox add-on. Please use these information below to contact the Firefox add-on developer.
Is Security Header Checker Safe?
Risk impact
Risk impact measures the level of extra permissions an extension has access to. A low risk impact extension cannot do much harms, whereas a high risk impact extension can do a lot of damage like stealing your password, bypassing your security settings, and accessing your personal data. High risk impact extensions are not necessarily malicious. However, if they do turn malicious, they can be very harmful.
Security Header Checker does not require any sensitive permissions.
Risk impact analysis details
- Low This permission has no access or impact on the user's system or data, thus carrying no risk.
Risk likelihood
Risk likelihood measures the probability that a Firefox add-on may turn malicious. This is determined by the publisher and the Firefox add-on reputation on Firefox Add-ons Store, the amount of time the Firefox add-on has been around, and other signals about the Firefox add-on. Our algorithms are not perfect, and are subject to change as we discover new ways to detect malicious extensions. We recommend that you always exercise caution when installing a Firefox add-on.
Security Header Checker may not be trust-worthy. Avoid installing if possible unless you really trust this publisher.
Risk likelihood analysis details
- Critical This extension is not longer available in the store
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