Add FAQ about enabling mastodon push notifications

It is not clear, as the FAQ shows for now, whether this works with just
desktop/computers or not - it is only possible to enable it on computers
(or if it's possible in mobile devices I did not see it though I only
checked with an iPhone).

This FAQ should probably be linked to in the guidelines later on as
right now it says that one should reload the feed as you do not get
notifications unless you are mentioned (assuming you have push
notifications enabled). As one of the pending changes post winners being
announced (02 August 2025 at 11 Pacific) is to clean up the guidelines,
rules and maybe the FAQ (that was rushed towards the end so as to not
delay IOCCC28 even longer) I have not done this.

Rebuilt faq.html. New image under png/.

FAQ version: 28.2.21 2025-07-31.

faq.html

@@ -453,7 +453,7 @@
 
 <!-- BEFORE: 1st line of markdown file: faq.md -->
 <h1 id="ioccc-faq-table-of-contents">IOCCC FAQ Table of Contents</h1>
-<p>This is FAQ version <strong>28.2.20 2025-06-11</strong>.</p>
+<p>This is FAQ version <strong>28.2.21 2025-07-31</strong>.</p>
 <h2 id="entering-the-ioccc-the-bare-minimum-you-need-to-know">0. <a href="#enter_questions">Entering the IOCCC: the bare minimum you need to know</a></h2>
 <ul>
 <li><strong>Q 0.0</strong>: <a class="normal" href="#enter">How can I enter the IOCCC?</a></li>
@@ -593,6 +593,7 @@
 <li><strong>Q 10.4</strong>: <a class="normal" href="#terms"> What is the current meaning of the IOCCC terms Author, Entry, and Submission?</a></li>
 <li><strong>Q 10.5</strong>: <a class="normal" href="#licence">Am I allowed to use IOCCC content?</a></li>
 <li><strong>Q 10.6</strong>: <a class="normal" href="#try_mastodon">What is Mastodon and why does the IOCCC use it?</a></li>
+<li><strong>Q 10.6.1</strong>: <a class="normal" href="#mastodon_notifications">How can I get push notifications when the judges post something on mastodon?</a></li>
 <li><strong>Q 10.7</strong>: <a class="normal" href="#tabstops">How do I set certain tabstops for viewing source code in vi(m)?</a></li>
 <li><strong>Q 10.8</strong>: <a class="normal" href="#menus">How do the menus on the website work and what can I do if they don’t work?</a></li>
 <li><strong>Q 10.9</strong>: <a class="normal" href="#author-information">How do I find more information about a winning author of an entry?</a></li>
@@ -6012,6 +6013,22 @@ follow posts something so you will have to check the IOCCC feed manually.</p>
 mastodon feed</a> page and/or mastodon
 app from time to time to view IOCCC mastodon updates.</p>
 <p>Jump to: <a href="#">top</a></p>
+<div id="mastodon_notifications">
+<h3 id="q-10.6.1-how-can-i-get-push-notifications-when-the-judges-post-something-on-mastodon">Q 10.6.1: How can I get push notifications when the judges post something on mastodon?</h3>
+</div>
+<p>To do this you need to go to the <a href="https://fosstodon.org/@ioccc">IOCCC mastodon
+account</a> with a computer (it is unclear how to do
+this with a mobile device, if it is even possible) and then you should see a
+bell icon. Make sure it’s activated. If you mouse over it when it’s not enabled
+it should look something like this, assuming of course we follow you! :-) (if
+not the message about following each other won’t show up):</p>
+<p><img src="png/mastodon-notifications.png"
+ alt="screenshot of Mastodon push notifications"
+ width=912 height=556></p>
+<p>It is not yet clear if this only works on desktop/computers or mobile devices
+too as it was only just discovered (31 July 2025) but whatever the case we
+suggest you do it.</p>
+<p>Jump to: <a href="#">top</a></p>
 <div id="tabstops">
 <h3 id="q-10.7-how-do-i-set-certain-tabstops-for-viewing-source-code-in-vim">Q 10.7: How do I set certain tabstops for viewing source code in vi(m)?</h3>
 </div>