See: https://drafts.csswg.org/css-page-3/#page-orientation-prop

Allows for changing orientation post-layout so that pages (particularly named pages) can be displayed in a different orientation.

We will need this as part of work to improve printing workflows for G Suite (now Google Workspace).

https://hg.mozilla.org/mozilla-central/rev/f17459f7537c

MDN work can be tracked here - https://github.com/mdn/content/issues/24390

Has this been released in Nightly, even behind a flag?
I have tried this with & without this flag, in 112.0a1 (2023-02-16) (64-bit) (MacOS): layout.css.page.orientation.enabled
Here is an example codepen this is working as I would expect in Chrome Version 110.0.5481.100 (Official Build) (x86_64)

(In reply to Noemi Erli[:noemi_erli] from comment #5)

https://hg.mozilla.org/mozilla-central/rev/f17459f7537c

Has this been released in Nightly.
See comment - https://bugzilla.mozilla.org/show_bug.cgi?id=1673987#c7

Will defer to jwatt if I am wrong, but I believe we expect this to be enabled for multiple pages-per-sheet currently, and in Nightly only.

(In reply to Emily McDonough [:alaskanemily] from comment #9)

Will defer to jwatt if I am wrong, but I believe we expect this to be enabled for multiple pages-per-sheet currently, and in Nightly only.

Thank you

Documentation, Data & BCD updated/added

• Content PR
• BCD PR
• Data PR

Just need to add this to Experimental_Features or release notes, awaiting on confirmation from jwatt.

There appears to be some inconsistencies with the way this feature is working in Firefox Nightly.
Firstly it adds an empty page at the end of the print output, this does not happen on Chromium based browsers.
Secondly the layout with the page headers and footers respects the orientation but the page itself does not

I have attached 2 PDFs to show this:

• page-orientation-example-from-firefox-nightly.pdf
• page-orientation-example-from-chrome.pdf

Test URL: https://developer.mozilla.org/en-US/docs/Web/CSS/@page/page-orientation#result

I have verified this fix in Nightly v122.0a1. This fix was introduced in Nightly v118.0a1 from 22-08-2023 in bug 1833244. The steps of verification are:

1. Load https://developer.mozilla.org/en-US/docs/Web/CSS/@page/page-orientation#result
2. Print the "Section in Portrait/Upright" frame
   Fixed behavior: All pages are displayed in portrait, but page 2 content is rotated to the left and page 3 content is rotated to the right.
   Faulty behavior: All pages are displayed in portrait, but all 2 pages display the content upright.
   Changeset: https://hg.mozilla.org/mozilla-central/rev/e5eaba75408a

Unfortunately, it appears that the fix only works on the Nightly channel because the Beta v121.0b8 and Release v120.0.1 and v119.0.1 still reproduce the issue just like a Nightly before the fix. Is this expected/intended, Jonathan? Tests were performed on Windows 10, MacOS 11 and Ubuntu 22 and the results were the same. Thank you!

It's expected, because the behavior has been behind a pref. Bug 1869880 has just landed a pref change to allow this behavior to ride the trains. For current Beta/release, you can enable the pref manually.