type-break-warning-countdown-string

type-break-warning-countdown-string is a variable defined in `type-break.el'.
Its value is

nil

Documentation:
If non-nil, this is a countdown for the next typing break.

This variable, in conjunction with `type-break-warning-countdown-string-type'
(which indicates whether this value is a number of keystrokes or seconds)
is installed in `mode-line-format' to notify of imminent typing breaks.