In this example document, ...
The document is a .docx file. It might be more sensible to save this in .odt format.
... each footnote number was inserted manually in LibreOffice Writer. Now, is there a way to convert them all to automatically, sequentially numbered footnotes?
I don't see an automatic method, but there is a manual techniques that is quite straightforward.
o Either: place the cursor on the first footnote anchor, so that it changes from I-beam to a hand, and go to right-click | Footnote/Endnote... .
o Or: place the cursor immediately to the left of the first footnote anchor and go to Edit | Footnote/Endnote... .
o In the Edit Footnote/Endnote dialogue, the Numbering type is shown as Character; change this to Automatic.
o *Don't* click OK, but instead click the right-arrow at bottom right to move to the next footnote anchor.
o Repeat the process, clicking Automatic and the right-arrow each time.
o When the right-arrow becomes greyed out, you have come to the end of the footnote anchors; click OK.
o The label in the footnote now labelled "D" has different format from the others, as it has a different paragraph style. Open the Styles and Formatting window and correct this.
o The footnotes are now labelled A, B, C, etc. If you want to change this - perhaps to the conventional 1, 2, 3, etc. - go to Tools | Footnotes/Endnotes... | Footnotes | AutoNumbering
Numbering and make your choice.
I trust this helps.
Brian Barker