src/vs/workbench/contrib/terminal/browser/xterm/commandNavigationAddon.ts/CommandNavigationAddon/_isMarkerInViewport
class CommandNavigationAddon:	private _isMarkerInViewport(terminal: Terminal, marker: IMarker) {
		const viewportY = terminal.buffer.active.viewportY;
		return marker.line >= viewportY && marker.line < viewportY + terminal.rows;
	}