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)


var style = document.createElement("style");
      var stylePromise = getAnnotationLayerStyle();
      foreignObject.appendChild(style);
      var div = document.createElement("div");
      div.className = "annotationLayer";
      
      stylePromise
        .then(async (common, overrides) => {
          style.textContent = common + overrides;
          var annotation_viewport = viewport.clone({ dontFlip: true });
          var parameters = {
            viewport: annotation_viewport,
            div,
            annotations,
            page,
            linkService: new pdfjsViewer.SimpleLinkService(),
            imageResourcesPath,
            renderInteractiveForms,
          };
          pdfjsLib.AnnotationLayer.render(parameters);
          
          var images = div.getElementsByTagName("img");
          var imagePromises = inlineAnnotationImages(images);
          await Promise.all(imagePromises).then(function (data) {
            var loadedPromises = [];
            for (var i = 0, ii = data.length; i < ii; i++) {
              images[i].src = data[i];
              loadedPromises.push(
                new Promise(function (resolveImage, rejectImage) {
                  images[i].onload = resolveImage;