React.addons provides CSSTransitionGroup for easily implementing basic CSS animations and transitions.
TransitionGroup and CSSTransitionGroup have been deprecated (https://reactjs.org/docs/addons.html#deprecated-add-ons)
TransitionGroup and CSSTransitionGroup have been deprecated (https://reactjs.org/docs/addons.html#deprecated-add-ons)
Yep! They have been deprecated in favor of their drop-in replacements.