"When the timeRemaining() method is invoked on an IdleDeadline object it MUST return the duration, as a DOMHighResTimeStamp, between the current time and the time associated with the IdleDeadline object."
It then goes on to describe a different algorithm for computing the return value of timeRemaining. I think the above-quoted line is misleading and should be removed.
This section:
https://w3c.github.io/requestidlecallback/#the-idledeadline-interface
... says:
"When the timeRemaining() method is invoked on an IdleDeadline object it MUST return the duration, as a DOMHighResTimeStamp, between the current time and the time associated with the IdleDeadline object."
It then goes on to describe a different algorithm for computing the return value of timeRemaining. I think the above-quoted line is misleading and should be removed.