There might be more chance of getting the tag implemented in CommonMark than Markdown for similar reasons to the reasons that CommonMark is called &quot;CommonMark&quot;.<p>CommonMark: <a href="http:&#x2F;&#x2F;commonmark.org&#x2F;" rel="nofollow">http:&#x2F;&#x2F;commonmark.org&#x2F;</a><p>Markdown: <a href="http:&#x2F;&#x2F;daringfireball.net&#x2F;projects&#x2F;markdown&#x2F;syntax" rel="nofollow">http:&#x2F;&#x2F;daringfireball.net&#x2F;projects&#x2F;markdown&#x2F;syntax</a>