Browser & Web Performance · Junior · Question 71 of 75

What does the `Strict-Transport-Security` (HSTS) header do?

1Blocks all third-party scripts
2Encrypts cookies on the client
✓Correct answer: Tells the browser to use only HTTPS for this site for a set period

Explanation

After the first visit the browser upgrades http:// links itself, which prevents SSL-stripping on later visits.

Further reading

MDN: Strict-Transport-Security ↗

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