Your bug report

#21188: Preview installed from the package manager changes LaTeX-mode-hook

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 21188@debbugs.gnu.org.

-- 
21188: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=21188
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