1859230 - On Mac Sonoma, using variable fonts with COLRv1/SVGinOT emoji results in wrong x-height

Status: RESOLVED INCOMPLETE

(Core :: Layout: Text and Fonts, defect)

Description

[Jules Ng]

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:109.0) Gecko/20100101 Firefox/119.0

Steps to reproduce:

On Mac Sonoma, install a COLRv1/SVGinOT emoji font. In Firefox, set font.name-list.emoji in about:config or change font-family in css to use that emoji. Use that emoji in a text with a variable font.

Sample COLRv1 emoji I used was Noto Color Emoji, specifically Noto-COLRv1.ttf from: https://github.com/googlefonts/noto-emoji/tree/main/fonts

Sample SVGinOT emoji I used was Twitter Color Emoji, specifically TwitterColorEmoji-SVGinOT.ttf from: https://github.com/13rac1/twemoji-color-font (you can run brew install font-twitter-color-emoji)

Sample variable fonts I used included system-ui, and Inter Variable from: https://github.com/rsms/inter/releases/tag/v4.0-beta9h

Actual results:

Wrong x-height is observed when variable fonts are used with COLRv1/SVGinOT emoji. More precisely, the x-height is lower than without the emoji for both the fonts I tried.

I noticed this after bug 1856035 has been fixed.

Expected results:

The font should be rendered with correct x-height when using with COLRv1/SVGinOT emoji. Correct x-height is observed when used with SBIX emoji like Apple Color Emoji or Tossface (https://github.com/toss/tossface/releases/tag/v1.6).

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Core::Layout: Text and Fonts' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 2

[BugBot [:suhaib / :marco/ :calixte]]

The severity field is not set for this bug.
:jfkthame, could you have a look please?

For more information, please visit BugBot documentation.

Comment 3

[Jonathan Kew [:jfkthame]]

Jules, could you please attach a simple testcase or point to a webpage that illustrates the issue you're describing? That would help in reproducing and understanding what's going on. Thank you!

Comment 4

[BugBot [:suhaib / :marco/ :calixte]]

A needinfo is requested from the reporter, however, the reporter is inactive on Bugzilla. Given that the bug is still UNCONFIRMED, closing the bug as incomplete.

For more information, please visit BugBot documentation.