Your bug report

#20301: 11.88.3; mathtools.el: multlined environment inserts a spurious newline

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 20301@debbugs.gnu.org.

-- 
20301: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=20301
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