Your bug report

#60298: 30.0.50; switch-to-buffer-other-window opens new frame when split-window-preferred-function is split-window-vertically

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 60298@debbugs.gnu.org.

-- 
60298: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=60298
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