Your bug report

#63345: 28.2; provided-mode-derived-p doesn't work when passed an alias in MODES

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 63345@debbugs.gnu.org.

-- 
63345: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=63345
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