We’re seein an issue when attempting to print documents that are in landscape orientation. The document is processed, then sent to the native print window with portrait orientation. Changing between portrait and landscape manually in the print options doesn’t help either.
I apologize. As you note, it will print fine. The issue seems to be the print preview. When the orientation is set to portrait it will print correctly, The preview will have the pages displayed sideways, as it should for portrait, but this makes it harder to visualize the final print job. Preferably it would be displayed in landscape mode. When manually choosing landscape the content will still be displayed sideways, yet the page itself is oriented correctly.
If I open the attached PDF (directly, from disk) in Chrome or Edge and press the print-button it will preview in landscape correctly (conversely, Chrome won’t let me choose orientation, Edge will show settings for Landscape and Portrait, but its selection won’t have any effect on the rendering). This is how I would like to see it in PDF.js Express Viewer as well.
We do not control the print preview or how browsers decide to display the preview, so there is a not a lot we can do. I still am not sure if I understand the issue though - every document I have tested with seems to work as expected.