title: Why react-intl is not stable when using formatDate with same argument on different computer time zones?
body: <p>I'm getting a timestamp from server </p>
  
  <pre><code>const date = 1420070399999
  </code></pre>
  
  <p>that in console yields:</p>
  
  <blockquote>
    <p>new Date(date) => Wed Dec 31 2014 23:59:59 GMT+0000 (UTC)</p>
  </blockquote>
  
  <p>Then apply to it the following permutations (here <code>moment</code> is <code>moment@2.22.1</code> and <code>intl</code> comes as property using <code>injectIntl</code> from <code>react-intl</code> package `):</p>
  
  <pre><code>  const momentSimple = moment.utc(date);
    const momentFormatted = momentSimple.format(dateFormat);
    const defaultFormatSimple = intl.formatDate(momentSimple);
    const defaultFormatFormatted = intl.formatDate(momentFormatted);
    const formattedFormatSimple = intl.formatDate(momentSimple, { year: 'numeric', month: 'long' });
    const formattedFormatFormatted = intl.formatDate(momentFormatted, { year: 'numeric', month: 'long' });
  </code></pre>
  
  <p>When my computer timezone is set to <strong>Toledo, USA</strong> (Central America Time) those variables (starting from second, excluding the first one) have the following values:</p>
  
  <pre><code>"December 2014"
  "12/31/2014"
  "11/30/2014"
  "December 2014"
  "November 2014"
  </code></pre>
  
  <p>But when I switch to <strong>Tokyo, Japan</strong> I am getting this:</p>
  
  <pre><code>"December 2014"
  "1/1/2015"
  "12/1/2014"
  "January 2015"
  "December 2014"
  </code></pre>
  
  <p>As you can see there is Dec/Nov in Toledo and Jan/Dec in Tokyo. </p>
  
  <p><strong>Why is this so?</strong></p>