Surrounding footnote references in square brackets?

[nyanpasu64]

Wikipedia/MediaWiki surrounds footnote references in square brackets when generating HTML output (eg. [1]). Currently, pulldown-cmark's pub mod html (and Zola using it) only output the number itself, which is small and difficult to click, and makes adjacent footnote numbers run together unless I add a space in between:

https://github.com/raphlinus/pulldown-cmark/blob/5c7881c45c1b9cb35e8c9417f09521f7a517b8cf/src/html.rs#L120-L128

I can use CSS ::before/after { content: "[ ]" } to add visual brackets to separate footnotes. However, this does not affect the text you can select and copy elsewhere. Copy-pasting the text as HTML causes the problem to reappear, and when copy-pasting as plain-text, all footnotes run together with body text.

Is it possible to add an option to add [ and ] (or alternatively, configurable characters) around footnotes when converting to HTML?