Your bug report

#78153: 31.0.50; 'indent-region M-C-\ but it is C-M-\

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 78153@debbugs.gnu.org.

-- 
78153: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=78153
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