Bug 96982 – Please add support for OpenType alternative style sets, as requested via [-webkit-]font-feature-settings

• Status: NEW
• Component: Text

[Henri Sivonen]

Builds tested: Safari 6.0 and WebKit nightly for 2012-09-17 both on OS X 10.8.1.

Steps to reproduce:
1) Load http://hsivonen.iki.fi/webm-share/
2) Search for the word “Wikipedia”.
3) Compare the letter ‘W’ in the words “Wikipedia” and “WebM”.

Actual results:
The ‘W’ in both “Wikipedia” and “WebM” looks the same.

Expected results:
Expected the ‘W’ in “Wikipedia” to have 4 top serifs as in Firefox, Chrome and IE10 and the ‘W’ in “WebM” to have 3 top serifs.

Additional information:
There is markup

<span class="wiki">W</span>ikipedia

and style

.wiki {
  -webkit-font-feature-settings: "ss05" 1;
  -moz-font-feature-settings: "ss05" 1;
  -ms-font-feature-settings: "ss05" 1;
  -o-font-feature-settings: "ss05" 1;
  font-feature-settings: "ss05" 1;
}.


The font subset was created using the popular https://bitbucket.org/philip/font-optimizer/ tool. FontForge complains about one erroneous ligature, but the resulting font passes OpenType sanitization in Firefox and Chrome. Firefox, Chrome, IE10 and Safari are all happy enough with the GPOS table to use ligatures for e.g. “Th” and “Qu”. Even if the font had a minor technical defect, Safari should render the the alternative glyph properly for compatibility with other browsers.

[Alexey Proskuryakov]

I'm told that we don't support font-feature-settings yet, so it's not just one specific case.

[Shiki Suen]

I tested WebKit-SVN-r197635 nightly build and have found it supports at least 'palt' feature.