At least some content in this article is derived from information featured in Fantastic Beasts: Cases from the Wizarding World. Spoilers will be present within the article.
She took it with her on her expedition to the Austrian Alps to look for a Yeti. When she followed tracks into Percival Shacklehorn's tent and something subsequently attacked and she was forced to hide in a grandfather clock, her bag was left behind outside. Mathilda Grimblehawk and her partner magically picked open the lock and examined the contents of the bag, as part of their investigation of the events.