Your bug report

#57207: 29.0.50; Fontification is slow after e7b5912b23 (Improvements to long lines handling)

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 57207@debbugs.gnu.org.

-- 
57207: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=57207
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