This a very simple extension that triggers configurable commands after a period of inactivity, i.e. when you stop typing.
When commands are configured for current file extension, a button is displayed in the status bar (a watch with a tick or a cross next to it) indicating if On Idle is enabled for that file extension:
Click the button to disable or enable.
The position of the status bar button can be configured using
You can install the latest version of the extension via the Visual Studio Marketplace here.
The source code is available on GitHub here.