Flutter webapp show blank screen on Safari "Private browsing mode" caused by "Hive.openBox() " is not be executed.

**Steps to Reproduce**
- Just init a flutter project with Hive database as normally
`var box = await Hive.openBox('testBox');`
- Build flutter webapp in release mode
- Open the webapp on the safari "Private browsing mode"
- The web will display a blank screen
- In the console log, I saw the app stuck on that line `var box = await Hive.openBox('testBox');`
- If we wait for a litter, and reload the browser -> the Hive box could open, and the app run as normal.
- I think in private browsing, the indexed database needs a litter time to create. So the first time the code will not work.

**Code sample**
```
var box = await Hive.openBox('testBox');
```

**Version**
- Platform: iOS, Mac
- Flutter version: 2.0.0
- Hive version: 2.0.4