Electron/Browser JS crash, SplashScreenProxy

# Bug Report

### Command or Code
```
cordova plugin add cordova-plugin-splashscreen@latest
cordova platform add electron@latest
cordova run electron --nobuild

```
```

```

### What does actually happen?
```
adding proxy for SplashScreen
SplashScreenProxy.js:80 Uncaught TypeError: Cannot read property 'appendChild' of null
at Object.show (SplashScreenProxy.js:80)
at showAndHide (SplashScreenProxy.js:143)
at SplashScreenProxy.js:158
at XMLHttpRequest.xhrStatusChangeHandler (cordova.js:902)
```

### Environment, Platform, Device
cordova@9.0.0
cordova-lib@9.0.1
cordova-plugin-splashscreen@5.0.3
cordova-electron@1.1.1.

## Checklist

- [X] I searched for existing GitHub issues
- [X] I updated all Cordova tooling to most recent version
- [X] I included all the necessary information above

Reproduce the issue with the listed cordova plugin, platform, and run commands, then inspect SplashScreenProxy.js around show at line 80 and its callers showAndHide and the initialization near line 158. Trace why the element used by appendChild is null in the Electron/browser environment; done means the splash screen no longer crashes and the reported commands run successfully.

Written by the indexing model from the issue text.