CLICK delays running the block body until the ▶ run button is clicked, possibly many times.
Our first demo of interactive markup listened for clicks and ran the nested blocks whenever desired.
The ▶ button appears when CLICK first runs. A shift-click will turn on advanced reporting while the block body runs. State read by subsequent blocks will be reported inline. Often additional console.log output will be enabled. See also TICK.
CLICK HELLO
CLICK writes state.debug true of false depending on the shiftKey state at time of click.