Attach (recommended) or Link to PDF file here:
https://guichet.public.lu/dam-assets/catalogue-formulaires/tva/tva-option-aic-pers-morales/tva-option-aic-pers-morale-DE.pdf

Configuration:
- Web browser and its version: Firefox Nightly 91.0a1 (2021-06-26) (64-bit)
- Operating system and its version: Windows 10.0.19043.1052
- PDF.js version: N/A

Steps to reproduce the problem:
1. enableXFA in Firefox Nightly
2. Open form

What is the expected behavior? (add screenshot)
Header image is scaled properly
![image](https://user-images.githubusercontent.com/7104454/123525954-905d1f00-d6a2-11eb-840e-be30eee395e1.png)

What went wrong? (add screenshot)
Image is scaled to fit
![image](https://user-images.githubusercontent.com/7104454/123525957-96530000-d6a2-11eb-9991-bf7f37c6f1a5.png)


"code93",
        "code128",
        "code128a",
        "code128b",
        "code128c",
        "code128sscc",
        "datamatrix",
        "ean8",
        "ean8add2",
        "ean8add5",
        "ean13",
        "ean13add2",
        "ean13add5",
        "ean13pwcd",
        "fim",
        "logmars",
        "maxicode",
        "msi",
        "pdf417",
        "pdf417macro",
        "plessey",
        "postauscust2",
        "postauscust3",
        "postausreplypaid",
        "postausstandard",
        "postukrm4scc",
        "postusdpbc",
        "postusimb",
        "postusstandard",
        "postus5zip",