SUGGESTION: Allow alternative footnote tags (e.g. '…' rather than a number)

First: very nice work, great and clean implementation of this idea.
I’m wondering if you could incorporate (or guide me where in the code I can customize) the ability to choose other characters to demarcate footnotes.

Take a look at bigfootjs.com for a specific example.

https://wordpress.org/plugins/inline-footnotes/