Your bug report

#25599: 26.0.50; "Marker does not point anywhere" error signaled by primitive-undo near an overlay with an auto-removal insert-in-front-hooks value

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 25599@debbugs.gnu.org.

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25599: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=25599
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