Front-End’s Missing Metric: The TBT Window

· Harry Roberts · May 31, 2026, 10:23 a.m.
Web Development user-experience web-performance metrics
Summary
The post discusses the TBT Window, a useful metric that links First Contentful Paint (FCP) and Time to Interactive (TTI), highlighting that Total Blocking Time (TBT) can be affected by changes in FCP or TTI even without long tasks.
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