If you can not save your new created extension to a correct path then maybe a additional first entry in your project composer.json is needed.
"repositories": [ { "type": "path", "url": "./packages" }, ... ... ]
There will be now a „root“ storagePath an the extension could be saved in the correct location. In my case without this config it would be accidently saved nested into the folder of another extension.
![](https://www.motions-media.de/wp-content/uploads/2022/01/extension-builder-folder-with-config.png)
TYPO3 Version
10.4.23 composer mode
Extension Builder Version:
git v10.0.3