Tweak G13, on-input understanding, F37 (#4291)

* in G13, as radio buttons/inputs would cause 2.1.1 Keyboard failures
(as keyboard users are not able to explicitly select a radio button with
the keyboard without triggering a change event, which would then lead to
a form submission or page reload in these examples), changing the
examples to a `select` and a set of toggle buttons
* reformatting/cleanup of the markup for G13
* in on-input understanding, replacing the mention of radio buttons with
a select dropdown as well, for clarity/consistency (in this case, even
the radio button example would be fine, but it may confuse matters)
* in F37, add an extra note explicitly mentioning that radio buttons
will still fail 2.1.1 even *if* they included a warning that satisfies
3.2.2

Closes #898

---------

Co-authored-by: Kenneth G. Franqueiro <kfranqueiro@users.noreply.github.com>
Co-authored-by: Mike Gower <mikegower@gmail.com>

Author: 3 people

techniques/failures/F37.html

@@ -56,7 +56,10 @@ <h3></h3>
          </ol>
       </section>
       <section class="results"><h3>Expected Results</h3>
-         <p> If check #3 is false, then this failure condition applies and content
-                            fails the Success Criterion.</p>
+         <p>If check #3 is false, then this failure condition applies and content fails the success criterion.</p>
       </section>
-   </section><section id="related"><h2>Related Techniques</h2></section><section id="resources"><h2>Resources</h2></section></body></html>
+      <div class="note">Note that in the case of a set of radio buttons, it will pass the requirements of 3.2.2 if an indication or warning is added stating that selecting a radio button will result in a change of context; however,
+         this scenario would still likely fail 2.1.1 Keyboard, since it's not possible (in current user agents) for a user to
+         navigate through a set of radio buttons with the keyboard without triggering a change event.
+      </div>
+   </section><section id="related"><h2>Related Techniques</h2></section><section id="resources"><h2>Resources</h2></section></body></html>

techniques/general/G13.html

@@ -16,11 +16,12 @@
       </ul>
    </section><section id="examples"><h2>Examples</h2>
       <ul>
-         <li>A series of radio buttons at the top of a page include
-                options for German, French and Spanish. Instructions precede
-                the buttons that instruct the user that the language will be
+         <li>A select dropdown at the top of a page includes
+                options for German, French and Spanish. Instructions preceding
+                the dropdown instruct the user that the language will be
                 changed upon selecting an option.</li>
-         <li>A 50 question online survey displays one question at a time.
+         <li>A 50-question online survey displays one question at a time,
+                with each answer marked up as a toggle button.
                 Instructions appear at the beginning of the survey that
                 explain that users will be taken to the next question of the
                 survey upon selecting an answer to each question.</li>
@@ -43,4 +44,4 @@
       <li><a href="../general/G80">G80</a></li>
    </ul></section><section id="resources"><h2>Resources</h2>
 
-   </section></body></html>
+   </section></body></html>

understanding/20/on-input.html

@@ -102,14 +102,14 @@ <h2>Examples of On Input</h2>
       <ul>
 
          <li>
-            A form is provided for creating calendar entries in a web based calendaring and scheduling
-            application. Along with the standard fields for subject, time and location, there
-            is a set of radio buttons to select the type of calendar entry to create.  The calendar
-            entry type can be meeting, appointment or reminder.  If the user selects the radio
-            for meeting, additional fields are displayed on the page for entering the meeting
-            participants. Different fields appear if the reminder button is chosen. Because only
-            parts of the entry change and the overall structure remains the same the basic context
-            remains for the user.  
+            A form is provided for creating calendar entries in a web-based calendaring and scheduling
+            application. Along with the standard fields for subject, time and location, 
+            a select dropdown allows the user to choose the type of calendar entry to create. The calendar
+            entry type can be meeting, appointment or reminder.  If the user selects the
+            meeting option, additional fields are displayed on the page for entering the meeting
+            participants. Different fields appear if the reminder option is chosen. Because only
+            parts of the entry change and the overall structure remains the same, the basic context
+            remains for the user.
 
          </li>