nsZipArchive is not thread-safe by design, but we access omnijar from different threads.
Bug 1694885 Comment 0 Edit History
Note: The actual edited comment in the bug view page will always show the original commenter’s name and original timestamp.
[Omnijar.h](https://searchfox.org/mozilla-central/source/xpcom/build/Omnijar.h) is not thread-safe by design, but we access omnijar from different threads.