Add example with multiple targets to demo.

As the polyfill uses the window’s selection to highlight the target(s),
this only works in Firefox, as other browsers do not support selections
having multiple ranges.

demo.html

@@ -89,6 +89,9 @@
                     <li>
                         <a href="#:~:text=Aliquam%20urna,scelerisque.">Text between two phrases in different block elements</a>
                     </li>
+                    <li>
+                        <a href="#:~:text=Phasellus%20tempus%20dui&text=venenatis%20leo&text=ipsum,-eget">Multiple pieces of text (only works in Firefox)</a>
+                    </li>
                     <li>
                         <a href="#:~:text=GATTACA,CATATTAC">Select text between start and end of a long, uninterrupted string <em>(fails)</em></a>
                     </li>