Whether the Terminal has been interacted with. Interaction means that the terminal has sent data to the process which depending on the terminal's mode. By default input is sent when a key is pressed or when a command or extension sends text, but based on the terminal's mode it can also happen on:
For more information on events that can send data see "DEC Private Mode Set (DECSET)" on https://invisible-island.net/xterm/ctlseqs/ctlseqs.html
Represents the state of a Terminal.