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            <b><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - &quot;Font-Variant-East-Asian: proportional-width&quot; does not work while being defined within &#64;font-face block in cooperation with unicode-range. (Font features specified in &#64;font-face blocks can't force us down the complex text codepath)"
   href="https://bugs.webkit.org/show_bug.cgi?id=155319#c27">Comment # 27</a>
              on <a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - &quot;Font-Variant-East-Asian: proportional-width&quot; does not work while being defined within &#64;font-face block in cooperation with unicode-range. (Font features specified in &#64;font-face blocks can't force us down the complex text codepath)"
   href="https://bugs.webkit.org/show_bug.cgi?id=155319">bug 155319</a>
              from <span class="vcard"><a class="email" href="mailto:shikisuen&#64;outlook.com" title="Shiki Suen &lt;shikisuen&#64;outlook.com&gt;"> <span class="fn">Shiki Suen</span></a>
</span></b>
        <pre>(In reply to <a href="show_bug.cgi?id=155319#c21">comment #21</a>)
<span class="quote">&gt; Actually, the original content had &quot;HiraKana, 'Hiragino Kaku Gothic ProN'&quot;
&gt; which means were were falling back to Hiragino Kaku Gothic ProN, except that
&gt; fallback font doesn't have font-variant-east-asian: proportional-width
&gt; enabled, so it is treated as a distinct font.</span >

You were absolutely not falling back to Hiragino Kaku Gothic ProN at first. You create an HTML which consists the following contents, and you could see that the &#64;font-face with Unicode Range also omits western font variants:

=================
&lt;!DOCTYPE html&gt;
&lt;html&gt;
  &lt;head&gt;
  &lt;meta charset=&quot;UTF-8&quot;&gt;
  &lt;title&gt;&quot;font-variant-east-asian&quot; in &quot;&#64;font-face&quot;&lt;/title&gt;
&lt;style&gt;

&#64;font-face {unicode-range: U+0061;   /* a */
font-family: SMALLCAPS-A; src: local('Georgia'); font-variant: small-caps;}
sample {font-family: SMALLCAPS-A, Helvetica;}
sample2 {font-family: Georgia; font-variant: small-caps;}

&lt;/style&gt;
  &lt;/head&gt;
  &lt;body&gt;
      &lt;h1&gt;&lt;/h1&gt;
    &lt;p&gt;&lt;sample&gt;
    Idea.
    &lt;/sample&gt;&lt;/p&gt;
    &lt;p&gt;&lt;sample2&gt;
    Idea.
    &lt;/sample2&gt;&lt;/p&gt;
  &lt;/body&gt;
&lt;/html&gt;</pre>
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