RHEL 9.2 + latest update using firefox-115.3.1-1.el9_2.x86_64 doing

mkdir /tmp/foo
firefox --new-instance --profile /tmp/foo about:about

and then enabling Menu Bar and selecting File -> Print opens a print preview with text "Preparing Preview" and it takes roughly two minutes for the print preview to appear.

This should happen in an instant and takes much longer than it did in the past.

strace doesn't give any clear hints, SELinux was in Permissive during the test, no other slowness observed. Chromium is also slow with print review but with the preview takes perhaps "only" 30 seconds so this might be due to some underlying common component.