Long-form written content often have lots of endnotes/footnotes. The CMS editor should have a feature that allows you to add a footnote number in superscript in the body of the text that either contains a two-way link to a bibliography at the bottom of the page (as in Wikipedia articles) or opens a tooltip with the footnote on hover/click.

This feature is essential for blog/essay-style content. Readers want to check sources for credibility without having to manually scroll to the bottom of the page and then find their place in the text again.

Custom code tools such as Refokus' rich-text-enhancer allows you to emulate this system in a very crude sense, by adding [#id] links within the rich-text, but this is incredibly time-consuming, especially for longer articles with lots of references.