Your bug report

#25172: 26.0.50; Concurrency feature, sit-for doesn't work (crashing and unexpected behaviour)

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 25172@debbugs.gnu.org.

-- 
25172: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=25172
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