Re: [csswg-drafts] [css-fonts] `system-ui` behavior is undesired for some users (#3658)

Mandatory:

- Discourage the abuse of system UI in the specifications or MDN

Should we do?

- Force PC/AT OSes (Win/Linux/Android) to emulate Apple OSes' behavior (virtual Pan-CJK fonts if `lang` is CJK) in the specifications—It is relatively easy in Windows because the font name of UI fonts are limited, but is it possible in Linux/Android?
- Add a test case like the above (`lang` attribute sensitiveness) to WPT

---

> no place on the web.

Does have place on Electron or WebView apps.

-----

> system-ui is dependent on operating system implementation, which may reference user locale and language settings, and provides varying level of text shaping support; this may cause the displayed typeface to be undesirable for some end users (e.g. Simplified Chinese users might get a monospaced serif font on older version of Windows). Note that some operating system vendors does not offer means to customise system-ui, unlike browser UAs that generally allow users to customise sans-serif or serif font family. As the name implies, system-ui should be used on UI elements in web application, and not for large paragraphs of text or articles.

> As the name implies, system-ui should be used on UI elements in web application, and should not…

↓

1. As the name implies, system-ui is _intended for use with_ UI elements in web applications, and should not be used…
2. As the name implies, system-ui should be _mainly_ used on UI elements in web applications, and should not be used…

> customise

↓

customize (Sorry for nit)


> text or articles.

↓

text or articles (e.g. on some devices running non-Apple operating systems, the glyph shape does not match what the language specified by the lang attribute expects unlike `sans-serif`).





-- 
GitHub Notification of comment by tats-u
Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/3658#issuecomment-3307734495 using your GitHub account


-- 
Sent via github-notify-ml as configured in https://github.com/w3c/github-notify-ml-config

Received on Thursday, 18 September 2025 14:20:28 UTC