Candace Payne was not expecting to purchase the mask when she went to her local Kohls department store, just outside of Dallas, Texas. She doesn't even consider herself a huge Star Wars fan.
On Thursday, the 37-year-old mother of two was returning some items and was going to spend her birthday money on some exercise clothes or something "for the kids".
The Facebook Live video she broadcast from the store's car park - immediately after purchasing the Chewbacca mask - has broken the record as the most-watched Facebook Live video - ever.
"That's just crazy," Mrs Payne told the BBC. "I'm just laughing - in all honesty, that is ridiculous. I've looked at the number of views and it just seems like someone is just playing with a calculator."
It's a big number: So far, more than 48 million people have watched Payne laugh hysterically as she shows Facebook her new purchase. (Update: As of early Saturday, the video has had 91 million views.)"
Source: BBC News, 20th May 2016
Note 1 - As of 23rd May the video has had 135m views - see it here
Note 2 - For absolute clarity, the video had very few views 'live' - almost all of these views came afterwards when it somehow went viral. 'Live' basically means that it was uploaded while it was being made, which is clearly the easiest thing to do.
Note 3 - Psy's Gentleman (follow up to Gangnam Style) reached 100m views in 4 days in 2013 - the fastest video ever to do so. So Candace Payne easily beat that.