how do I alter the font size of footnote superscripts?

Libra 5.4. seven pages

Not a lot of information in the question description!

You access the various “properties” of the notes engine through Tools>Footnotes & Endnotes. Here you will learn that anchor (i.e. the “superscript” number) formatting is controlled by character style Footnote Anchor, the same note tag in the bottom of the page is formatted with character style Footnote characters and that the note text is itself formatted by paragraph style Footnote.

The parameters for the endnotes are in tab Endnotes.

All you have to do is customise the various styles to fir your needs.

In case you have no idea what styles are and how they categorised, read the Writer Guide. This is the “standard” way of working with Writer.

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