Your bug report

#21766: 25.0.50; delete-trailing-whitespace sometimes deletes non-whitespace

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 21766@debbugs.gnu.org.

-- 
21766: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=21766
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