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on.update = function(dt)
	if Global_state.thread then
		update_all_editors(Global_state.thread, dt)
	end
	if Pan then
		set_mouse_cursor('hand')
		Viewport.x = Pan.x - App.mouse_x()/Viewport.zoom
		Viewport.y = Pan.y - App.mouse_y()/Viewport.zoom
		B()
	else
		set_mouse_cursor('arrow')
	end
end