Your bug report

#73607: 30.0.90; Strange behaviour of C-x with define-prefix-command

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 73607@debbugs.gnu.org.

-- 
73607: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=73607
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