Short description
A browser responds to user input by adding tasks to a queue on the main thread to be executed one by one. Any task taking 50 milliseconds or longer to execute is identified as a long running time.
New Relic event types
  • SyntheticRequest

    Data source: Synthetics
Units of measurement count

Google's User-centric Performance Metrics contains detailed information about its Paint Timing API and longRunningTasksCount.