src/vs/workbench/contrib/comments/browser/commentNode.ts/CommentNode/registerActionBarListeners
class CommentNode:	private registerActionBarListeners(actionsContainer: HTMLElement): void {
		this._register(dom.addDisposableListener(this._domNode, 'mouseenter', () => {
			actionsContainer.classList.remove('hidden');
			actionsContainer.classList.add('mouseover');
		}));
		this._register(dom.addDisposableListener(this._domNode, 'mouseleave', () => {
			if (actionsContainer.classList.contains('mouseover') && !actionsContainer.classList.contains('tabfocused')) {
				actionsContainer.classList.add('hidden');
			}
			actionsContainer.classList.remove('mouseover');
		}));
	}