PDFjs mispositions footer/header logos in this pdf, overlapping other content

[gijsk]

(The issue summary probably should be updated based on the technical cause of this issue.)

Attach (recommended) or Link to PDF file here:

https://www.christianaid.org.uk/sites/default/files/2020-04/Christian%20Aid%20Week%20Order%20of%20Service.pdf

Configuration:

• Web browser and its version: Firefox 75 release, 76 beta
• Operating system and its version: macOS
• PDF.js version: can reproduce on https://mozilla.github.io/pdf.js/web/viewer.html when downloading and opening the PDF there
• Is a browser extension: no, builtin to the browser.

Steps to reproduce the problem:

1. open PDF, scroll down to the bottom of the first page or top of the last page

What is the expected behavior?
Bottom of first page:

What went wrong?

Bottom of first page in pdfjs:

There is also a strange raster pattern visible on the entire PDF when viewed in pdfjs, but not in pdfium or Preview.app .

[Snuffleupagus]

Duplicate of #269

[timvandermeij]

Yes, this is because of missing layer support tracked in the issue above. Closing as a duplicate of that one; thanks!