Oxford University Press (OUP) publishes the following books, and couldn't have used Microsoft Word to variate the number of footnotes per line, because [harrymc](https://superuser.com/a/1520058) affirmed
>I have done some tests on Word 2019, and it seems that the option of "Footnote layout" is now dead and non-functional. [. . .] Your only option is to file a bug-report to Microsoft using the Feedback Hub, then wait for a fix.
So what programs might've OUP used? I emailed them, but they're on summer vacation.
The first screenshot is from[*Criminal Law: Text, Cases, and Materials* (8 edn, 2018)](https://global.oup.com/academic/product/criminal-law-9780198811817?cc=ca&lang=en&). p 180.
[![enter image description here][1]][1]
Same with [*Anson's Law of Contract* (31 edn 2020)](https://www.amazon.com/Ansons-Law-Contract-Jack-Beatson-dp-0198829973/dp/0198829973/ref=dp_ob_title_bk) p 180.
[![enter image description here][2]][2]
[1]: https://i.stack.imgur.com/8qLoY.jpg
[2]: https://i.stack.imgur.com/C1Y0V.jpg