Your bug report

#56545: guix time-machine/shell throws "unsupported manifest format" error

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 56545@debbugs.gnu.org.

-- 
56545: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=56545
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