My app encountered this crash in recent months.From the stacktrace as the following, I can‘t find any clue.This crash only happened on iOS 11.2.x and background thread. This bug almost happened only once on each user's device. I don't know if it is a bug from Apple.Can anybody give me some clues about this bug? Thanks a lot!
here is the stacktrace:
here is the device info for the bug:
