css.at-rules.page.size - Firefox and Safari don't actually support this

[willo-icon]

What type of issue is this?

Browser bug (a bug with a feature that may impact site compatibility)

What information was incorrect, unhelpful, or incomplete?

MDN shows that Safari and Firefox support the @page { size } rule with no caveats, but they actually don't seem to work. Here's caniuse's more accurate table:

What browsers does this problem apply to, if applicable?

No response

What did you expect to see?

Either lack of support, or notes about partial support.

Did you test this? If so, how?

Tested myself in Chrome, Firefox, and Safari. Firefox shows it correctly in the PDF preview, but the PDF it saves does not have the correct page size. Safari neither previews nor saves a PDF with the correct size.

Can you link to any release notes, bugs, pull requests, or MDN pages related to this?

Here are bug trackers for support:

• Firefox: https://bugzilla.mozilla.org/show_bug.cgi?id=286443
• Safari (WebKit): https://bugs.webkit.org/show_bug.cgi?id=63575
  • This was the best issue I could find related to it, not sure if there's a more comprehensive issue

Caniuse page: https://caniuse.com/css-paged-media

Do you have anything more you want to share?

No response

MDN URL

https://developer.mozilla.org/en-US/docs/Web/CSS/@page/size

MDN metadata

MDN page report details

• Query: css.at-rules.page.size
• Report started: 2024-04-26T00:13:12.445Z