Well, the story made its way into the English speaking world via google translate, which is pretty notorious for dicking up subtle things like word order and direct vs indirect objects. She gave them the printout. She the printout them gave. They gave the printout her.

The original article is now gone, but you can read the HN comments from the time. https://news.ycombinator.com/item?id=5864427

The details of the story seem unlikely and it was probably sloppy journalism, but I haven't found anything besides speculation that claims it happened otherwise.

It doesn't appear anything was lost in translation:

https://news.ycombinator.com/item?id=5864882

https://news.ycombinator.com/item?id=5864653

https://news.ycombinator.com/item?id=5864577

I think the likeliest case was that they searched her laptop, found an open tab with her Facebook messages, then printed the conversation.

That's fair. But "Border agents can read your private messages" conveys a rather different idea than "Border agents can read tabs you leave open".

It sure does, but that's still just speculation. I think the story carries more weight than my speculation. Ultimately, we'll never really know what happened.