(This was posted in the Bugs forum, but it was suggested by @TrentOster on Twitter that they be posted here)
1) Open a bag, such as Neera's Gem Bag. 2) Tap on the "Open Container" button.
Notice that if you tap on an area of the button that overlaps with the area that the "Done" button will occupy (generally the right half), it will automatically register a tap on the "Done" button and close the bag.
Workaround: Tap on the upper left corner of the open container button.