vbox-with-2-wrapping-labels-where-one-should-wrap reftest failing in 4.6.0

On my machine a single reftest is failing:

665/674 gtk:reftest / reftest vbox-with-2-wrapping-labels-where-one-should-wrap.ui                  FAIL            0.39s   0/1 subtests passed
22:46:07 TEST_OUTPUT_SUBDIR=x11 GSETTINGS_SCHEMA_DIR=/tmp/portage/gui-libs/gtk-4.6.0/work/gtk-4.6.0-build/gtk G_TEST_SRCDIR=/tmp/portage/gui-libs/gtk-4.6.0/work/gtk-4.6.0/testsuite/reftests G_ENABLE_DIAGNOSTIC=0 GIO_USE_VOLUME_MONITOR=unix REFTEST_MODULE_DIR=/tmp/portage/gui-libs/gtk-4.6.0/work/gtk-4.6.0-build/testsuite/reftests MALLOC_PERTURB_=189 GIO_USE_VFS=local G_TEST_BUILDDIR=/tmp/portage/gui-libs/gtk-4.6.0/work/gtk-4.6.0-build/testsuite/reftests GSETTINGS_BACKEND=memory GTK_CSD=1 GDK_DEBUG=default-settings GDK_BACKEND=x11 GTK_A11Y=test /tmp/portage/gui-libs/gtk-4.6.0/work/gtk-4.6.0-build/testsuite/reftests/gtk-reftest --tap -k -o /tmp/portage/gui-libs/gtk-4.6.0/work/gtk-4.6.0-build/testsuite/reftests/output /tmp/portage/gui-libs/gtk-4.6.0/work/gtk-4.6.0/testsuite/reftests/vbox-with-2-wrapping-labels-where-one-should-wrap.ui
----------------------------------- output -----------------------------------
# random seed: R02S01dbc024dd37ee825fadcffe7f9f8934
# GLib-GIO-DEBUG: _g_io_module_get_default: Found default implementation local (GLocalVfs) for ‘gio-vfs’
1..1
# Start of tmp tests
# Start of portage tests
# Start of gui-libs tests
# Start of gtk-4.6.0 tests
# Start of work tests
# Start of gtk-4.6.0 tests
# Start of testsuite tests
# Start of reftests tests
# Storing test result image at /tmp/portage/gui-libs/gtk-4.6.0/work/gtk-4.6.0-build/testsuite/reftests/output/x11/vbox-with-2-wrapping-labels-where-one-should-wrap.out.png
# Storing test result image at /tmp/portage/gui-libs/gtk-4.6.0/work/gtk-4.6.0-build/testsuite/reftests/output/x11/vbox-with-2-wrapping-labels-where-one-should-wrap.ref.png
# Storing test result node at /tmp/portage/gui-libs/gtk-4.6.0/work/gtk-4.6.0-build/testsuite/reftests/output/x11/vbox-with-2-wrapping-labels-where-one-should-wrap.out.node
# Storing test result node at /tmp/portage/gui-libs/gtk-4.6.0/work/gtk-4.6.0-build/testsuite/reftests/output/x11/vbox-with-2-wrapping-labels-where-one-should-wrap.ref.node
# Storing test result image at /tmp/portage/gui-libs/gtk-4.6.0/work/gtk-4.6.0-build/testsuite/reftests/output/x11/vbox-with-2-wrapping-labels-where-one-should-wrap.diff.png
not ok 1 /tmp/portage/gui-libs/gtk-4.6.0/work/gtk-4.6.0/testsuite/reftests/vbox-with-2-wrapping-labels-where-one-should-wrap.ui
# End of reftests tests
# End of testsuite tests
# End of gtk-4.6.0 tests
# End of work tests
# End of gtk-4.6.0 tests
# End of gui-libs tests
# End of portage tests
# End of tmp tests

vbox-with-2-wrapping-labels-where-one-should-wrap.ref.node

vbox-with-2-wrapping-labels-where-one-should-wrap.out.node

It looks like the reference expect the "Hi Ho" to be in one line, but is getting wrapped here.