Without advertising, without needing to give your personal data, with the minimum necessary permissions, this application (based on the Open Source Tool ZXing) allows to scan different codes (QR Code, EAN, etc…).
If the code is an Internet address (frequently used for QR Codes) the application will open the browser directly to this address.
If the code is a food barcode, the application can open the OpenFoodFacts site on the corresponding product card.
In any case, the code text can be copied to the clipboard for use in another application.