Your bug report

#40997: [raid] The bootloader can only be installed to a single drive

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

The explanation is attached below, along with your original report.
If you require more details, please reply to 40997@debbugs.gnu.org.

-- 
40997: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=40997
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