Your bug report

#64971: 30.0.50; string-pixel-width return value is affected by 'line-prefix

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 64971@debbugs.gnu.org.

-- 
64971: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=64971
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