Your bug report

#43595: 27.1; project.el: `project-known-project-roots' would be useful to have in the documented API

which was filed against the emacs package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to 43595@debbugs.gnu.org.

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43595: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=43595
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