add note about tweeted in 2019/mills

2019/mills/README.md

@@ -46,6 +46,14 @@ guidelines for the IOCCC?
 
 You decide. :-)
 
+**Historic note**: The award title use of the word "**tweeted**"
+should be regarded as a IOCCC anachronism.  Over the years the
+maximum size of a _tweet_ changed since this entry won the IOCCC.
+Moreover, the [IOCCC now uses Mastodon](../../faq.html#try_mastodon)
+instead of whatever someone (and especially those who appear to
+have poor impulse control) chooses to call the platform where people
+used to tweet.
+
 
 ## Author's remarks:
 

2019/mills/index.html

@@ -421,6 +421,13 @@ implementation-specific format, your mileage may vary.</p>
 <p>But can a machine learn to write like Shakespeare? Can it write rules and
 guidelines for the IOCCC?</p>
 <p>You decide. :-)</p>
+<p><strong>Historic note</strong>: The award title use of the word “<strong>tweeted</strong>”
+should be regarded as a IOCCC anachronism. Over the years the
+maximum size of a <em>tweet</em> changed since this entry won the IOCCC.
+Moreover, the <a href="../../faq.html#try_mastodon">IOCCC now uses Mastodon</a>
+instead of whatever someone (and especially those who appear to
+have poor impulse control) chooses to call the platform where people
+used to tweet.</p>
 <h2 id="authors-remarks">Author’s remarks:</h2>
 <h3 id="welcome-to-omlet">Welcome to OMLET! 🍳:</h3>
 <p>OMLET is the <em>Obfuscated Machine Learning Environment Toolkit</em>, a