What is the meaning of JavaScript idle time in Chrome Developer tools?
I got a very long idle time.

What is the meaning of JavaScript idle time in Chrome Developer tools?
I got a very long idle time.

Idle time is the time in which nothing is done.
You can check a similar question in which Rob W has answerd it.
Go to
about:blank, and get a new CPU profile. The result is probably a value for (idle) close to 100% and a bit of (program)