ckeditor5-1.0.x-dev/tests/modules/ckeditor5_plugin_elements_test/ckeditor5_plugin_elements_test.ckeditor5.yml

# cspell:ignore everyblock justblockquote
blockquote.combo:
  elements:
    - <blockquote data-justblockquote>
    - <$block data-everyblock>

headings.with.other.attributes:
  elements:
    - <h1 data-just-h1>
    - <h2 class="additional-allowed-class">
    - <h3 data-just-h3 data-just-h3-limited="i-am-the-only-allowed-value">
    - <h5 data-just-h5-limited="first-allowed-value second-allowed-value">

headings.use.class.any.value:
  elements:
    - <h1 class>
    - <h2 class>
    - <h3 class>
    - <h4 class>
    - <h5 class>
    - <h6 class>