There are two issues here:
- if IDB is blocked, then the promise never resolves when you log out (and call indexedDB.deleteDatabase) and the app remains in a permanently hung state
- why is IDB blocked? well, something seems to have changed in Chrome 70 such that doing these operations in a web worker causes the blocked error. The benefits of workerizing IDB is so small that I'd rather just remove it at this point.
