Criticalcss.com bot crawls websites to generate and validate critical CSS for faster loading times. The service helps developers improve website performance by optimizing above-the-fold content delivery.

At a glance

Operator: Critical CSS
Type: Monitoring

How Centinel checks it

User agent: The request calls itself this crawler. Anyone can send the same string.

Criticalcss.com publishes nothing Centinel can check a source against, so a match reports the name and leaves the source unconfirmed. The match tokens, verification domains, and address feeds are not published here.

Allowing or blocking it

The crawler object in the /validate response sets access_allowed to true only for a verified source that your tenant allowlists. A policy rule can allow or block this crawler by its category, Monitoring.

Back to the crawler catalog