Your bug report

#19281: 11.86; environment update fails when environment name contains \

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

The explanation is attached below, along with your original report.
If you require more details, please reply to 19281@debbugs.gnu.org.

-- 
19281: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=19281
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