Bug 286420 – [GTK] Japanese/Simplified Chinese characters should be rendered differently, but are rendered equal

• Component: WebKitGTK
• Status: REOPENED

[Deleted User]

Created attachment 473983 [details]
Example rendering characters with `lang="ja"` and `lang="zh-CH"`

STR: open the attached example.

Expected: the characters for `lang="ja"` are rendered differently from the one corresponding to `lang="zh-CH"`. I'm unfamiliar with Japanese/Chinese and base that assumption on https://searchfox.org/wubkat/rev/cbb8b220c0f1f1ceaf9bac84eafc71dc87f2fc46/LayoutTests/imported/w3c/web-platform-tests/svg/text/reftests/lang-attribute.svg#9.

Actual: the characters are rendered the same.

Chrome and Firefox both render them differently.


An example where the language attribute correctly affects the rendering in WebKit would be helpful for fixing bug https://bugs.webkit.org/show_bug.cgi?id=285993.

[Karl Dubost]

Created attachment 473994 [details]
rendering in safari, firefox, chrome

Mirko, the characters are rendered as expected in all browsers.

[Alexey Proskuryakov]

The rendering is indeed different on the attached Safari screenshot.

[Deleted User]

They differ with WebKitGtk's MiniBrowser on Ubuntu 24.04.

[Deleted User]

Created attachment 474018 [details]
Rendering with WebKitGTK's MiniBrowser on Ubuntu 24.04.

[Deleted User]

Created attachment 474019 [details]
Rendering with Epiphany on Ubuntu 24.04.

[Deleted User]

The screenshot showing different results for Safari indicates the font used by Safari differs from the font used by Firefox and Chrome, shown on the same screenshot.

[Deleted User]

Created attachment 474020 [details]
Example with Noto Sans font-family

[Deleted User]

Karl: can you please check with the attached Noto Sans example?

[Karl Dubost]

Do you mean locally installed Noto Sans?
This will not work because it protects against finger printing. 
Then after there is the notion of which Noto Sans you are linking to with @font-face

https://fonts.google.com/noto/specimen/Noto+Sans

Noto Sans has different versions according to the language. 

There is a special Noto CJK (aka Chinese Japanese Korean)
https://github.com/notofonts/noto-cjk
Are you using this one?

[Deleted User]

(In reply to Karl Dubost from comment #9)
> Do you mean locally installed Noto Sans?
> This will not work because it protects against finger printing. 

I wasn't aware of the finger-printing issue.

> Then after there is the notion of which Noto Sans you are linking to with
> @font-face
> 
> https://fonts.google.com/noto/specimen/Noto+Sans
> 
> Noto Sans has different versions according to the language. 
> 
> There is a special Noto CJK (aka Chinese Japanese Korean)
> https://github.com/notofonts/noto-cjk
> Are you using this one?

The test uses `font-family: Noto Sans` (see view-source:https://bug-286420-attachments.webkit.org/attachment.cgi?id=474020).
However, I understand that example may not be applicable to Safari.

Still, the issue exists with WebKitGTK, see https://bugs.webkit.org/attachment.cgi?id=474018.
It also occurs with a local WebKitGTK build with last week's WebKit source.

[Alexey Proskuryakov]

Let's track this as a WebKitGTK issue then.