Your bug report

#53606: 29.0.50; Very slow Customize buffer for bibtex-biblatex-entry-alist

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 53606@debbugs.gnu.org.

-- 
53606: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=53606
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