- From: Christoph Päper via GitHub <sysbot+gh@w3.org>
- Date: Thu, 08 Mar 2018 13:58:58 +0000
- To: public-css-archive@w3.org
JFTR, from the [Unicode FAQ](http://unicode.org/faq/vs.html#DisplaySupport) (with my highlighting): > Q: How should variation sequences be displayed? > > A: When they are valid variation sequences, they should be displayed as illustrated in the [Unicode code charts](http://www.unicode.org/charts/), the [emoji charts](http://www.unicode.org/emoji/charts/index.html), or in the [Ideographic Variation Database](http://www.unicode.org/ivd/). When a variation sequence is not valid or its display is not supported, the base character is displayed as usual, and the variation selector is invisible. See [Display of Unsupported Characters](http://unicode.org/faq/unsup_char.html). > Q: What changes does a browser developer need to make to support variation sequences? > > A: Browsers generally use a font fallback mechanism to display web pages. This allows users to read text when the font specified in the web page is unavailable or doesn't support all the characters that are referenced on that web page. A simple but insufficient mechanism is to display characters in a font up until the first character that can't be displayed. Such a mechanism fails with variation sequences. A better mechanism is to **treat a combining character sequence as a single entity for the purpose of font substitution**. Because variation selectors have the General_Category property value of `Nonspacing_Mark`, this treatment allows variation sequences to be handled correctly. -- GitHub Notification of comment by Crissov Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/1710#issuecomment-371493988 using your GitHub account
Received on Thursday, 8 March 2018 13:59:01 UTC