Your bug report

#40634: Massive pattern list handling with -E format seems very slow since 2.28.

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

The explanation is attached below, along with your original report.
If you require more details, please reply to 40634@debbugs.gnu.org.

-- 
40634: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=40634
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