@Override
  public @NotNull String getDemoText() {
    return """
      <?xml version='1.0' encoding='ISO-8859-1'  ?>
      <!DOCTYPE index>
      <!-- Some xml example -->
      <index version="1.0" xmlns:<bg><np>pf</np></bg>="http://test">
         <name>Main Index</name>
         <indexitem text="rename" target="refactoring.rename"/>
         <indexitem text="move" target="refactoring.move"/>
         <indexitem text="migrate" target="refactoring.migrate"/>
         <indexitem text="usage search" target="find.findUsages"/>
         <<matched>indexitem</matched>>Matched tag name</<matched>indexitem</matched>>
         <someTextWithEntityRefs>&amp; &#x00B7;</someTextWithEntityRefs>
         <withCData><![CDATA[
                <object class="MyClass" key="constant">
                </object>
              ]]>
         </withCData>
         <indexitem text="project" target="project.management"/>
         <<custom_tag_name>custom-tag</custom_tag_name>>hello</<custom_tag_name>custom-tag</custom_tag_name>>
         <<bg><np>pf</np></bg>:foo <bg><np>pf</np></bg>:bar="bar"/>
      </index>""";
  }
@Override
  public @NotNull String getDemoText()