Your bug report

#61629: master: Sometimes M-x imenu throws an error when there's a single function in the buffer.

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 61629@debbugs.gnu.org.

-- 
61629: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=61629
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