Your bug report

#31542: emacs-lisp-intro.texi - `M-.' does not call `find-tag' but `xref-find-definitions' after Emacs 25.1

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

The explanation is attached below, along with your original report.
If you require more details, please reply to 31542@debbugs.gnu.org.

-- 
31542: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=31542
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