Reproduce the lost signature

Preconditions

• Use NDKCacheAdapterDexie as the cacheAdapter for NDK

Reproduction steps

1. Run npm build and npm preview.
2. Open the page.
3. In the left part, all events have a signature.
4. Wait a few seconds, then refresh the page.
5. In the left part, some events do not have a signature.

Clearing indexdb can reproduce the issue again.