Hackers Help: Can I use a cross-brace to strengthen IKEA’s PAX wardrobe systems?

PAX | IKEA.com
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Photo: IKEA.com

I got two second-hand PAX wardrobes, and they are kind of fragile, so I am looking into ways to stabilize them. I thought a cross-brace could be a good option; at least it is used on IKEA’s bookshelves. But, can I also use cross-braces on the wardrobe system?