[css-writing-modes] Mark upright issue <https://lists.w3.org/Archives/Public/www-style/2015May/0004.html>

Author: kojiishi

css-writing-modes/Overview.bs

@@ -1323,6 +1323,8 @@ Vertical Typesetting and Font Features</h4>
       (E.g. the OpenType ''vert'' feature must be enabled.)
       Furthermore, characters from horizontal cursive scripts (such as Arabic)
       are shaped in their isolated forms when typeset upright.
+      <p class="issue"><a href="https://lists.w3.org/Archives/Public/www-style/2015May/0004.html">Proposal to weaken to should</a>,
+        see also ''upright''.
 
       <p class="note">Note that even when typeset "upright",
         some glyphs should appear rotated.