Invalid CultureInfo no longer throws CultureNotFoundException
<p>Creating a culture info with <code>es-CA</code>, <em>which obviously</em> is incorrect <strong>should</strong> throw an exception, but no longer does.</p>

<p>This <em>previously</em> threw a <code>CultureNotFoundException</code>: <code>new CultureInfo("es-CA")</code>. It now seem to fall back to <code>es</code> with an "Unknown Locale". Although, doing something like <code>xy-ZZ</code> also works, which it's rather odd?</p>

<p>Why does this no longer throw an exception? Was this changed in a recent version of .NET? </p>

<p><strong>Update 1</strong></p>

<p>The documentation mentions the following:</p>

<blockquote>
  <p>if the <strong>operating system does not support that culture</strong>, and if name is not the name of a supplementary or replacement culture, the method throws a CultureNotFoundException exception.</p>
</blockquote>

<p>Testing this on Windows 7, it throws <code>CultureNotFoundException</code> but on Windows 10 it does not throw the exception.</p>