Trying to measure GtkPopover 0x42761b0 for height of 277, but it needs at least 313

Steps to reproduce:

Open gtk4-node-editor
Click the "Save testcase" button in the headerbar
Observe stderr: with repeated printing of:

(gtk4-node-editor:75992): Gtk-WARNING **: 02:29:17.935: Trying to measure GtkPopover 0x42761b0 for height of 277, but it needs at least 313

(gtk4-node-editor:75992): Gtk-WARNING **: 02:29:17.954: Trying to measure GtkPopover 0x42761b0 for height of 277, but it needs at least 313

(gtk4-node-editor:75992): Gtk-WARNING **: 02:29:17.972: Trying to measure GtkPopover 0x42761b0 for height of 277, but it needs at least 313

I think that showed up after the recent sizing changes by @bugaevc but I hadn't updated to git main for a while.

The stack trace is not very enlightening:

_g_log_abort (breakpoint=<optimized out>) at ../glib/gmessages.c:431                                                                                                                          
431	    G_BREAKPOINT ();
(gdb) where
#0  _g_log_abort (breakpoint=<optimized out>) at ../glib/gmessages.c:431
#1  g_log_writer_default (log_level=<optimized out>, fields=0x7fffffffc1e0, n_fields=6, user_data=0x0) at ../glib/gmessages.c:2953
#2  0x00007ffff70c9c68 in g_log_structured_array (log_level=G_LOG_LEVEL_WARNING, fields=0x7fffffffc1e0, n_fields=6) at ../glib/gmessages.c:1874
#3  g_log_structured_array (log_level=log_level@entry=G_LOG_LEVEL_WARNING, fields=fields@entry=0x7fffffffc1e0, n_fields=n_fields@entry=6) at ../glib/gmessages.c:1847
#4  0x00007ffff70ca037 in g_log_structured_standard
    (log_domain=0x7ffff7a21417 "Gtk", log_level=G_LOG_LEVEL_WARNING, file=<optimized out>, line=<optimized out>, func=<optimized out>, message_format=<optimized out>)
    at ../glib/gmessages.c:1931
#5  0x00007ffff7419526 in gtk_widget_measure
    (widget=0x643560, orientation=GTK_ORIENTATION_HORIZONTAL, for_size=277, minimum=0x7fffffffc8b8, natural=0x0, minimum_baseline=0x0, natural_baseline=0x0) at ../gtk/gtksizerequest.c:497
#6  0x00007ffff73c2732 in gtk_popover_native_layout (native=0x643560, width=397, height=277) at ../gtk/gtkpopover.c:719
#7  0x00007ffff73ea267 in gtk_native_layout (self=0x643560, width=397, height=277) at ../gtk/gtknative.c:112
#8  0x00007ffff73ea294 in surface_layout_cb (surface=0x1d55800, width=397, height=277, native=0x643560) at ../gtk/gtknative.c:121
#13 0x00007ffff7046303 in <emit signal 'layout' on instance ???> (instance=<optimized out>, signal_id=<optimized out>, detail=<optimized out>) at ../gobject/gsignal.c:3597
    #9  0x00007ffff7743d5d in _gdk_marshal_VOID__INT_INTv (closure=0xf6dc30, return_value=0x0, instance=0x1d55800, args=0x7fffffffcc20, marshal_data=0x0, n_params=2, param_types=0x676070)
    at gdk/gdkmarshalers.c:479
    #10 0x00007ffff7046133 in _g_closure_invoke_va (closure=0xf6dc30, return_value=0x0, instance=0x1d55800, args=0x7fffffffcc20, n_params=2, param_types=0x676070)
    at ../gobject/gclosure.c:896
    #11 signal_emit_valist_unlocked (instance=instance@entry=0x1d55800, signal_id=signal_id@entry=235, detail=detail@entry=0, var_args=var_args@entry=0x7fffffffcc20)
    at ../gobject/gsignal.c:3438
    #12 0x00007ffff7046248 in g_signal_emit_valist (instance=0x1d55800, signal_id=235, detail=0, var_args=var_args@entry=0x7fffffffcc20) at ../gobject/gsignal.c:3277
#14 0x00007ffff7828162 in gdk_surface_layout_on_clock (clock=0x628360, data=0x1d55800) at ../gdk/gdksurface.c:1405
#19 0x00007ffff7046303 in <emit signal 'layout' on instance ???> (instance=<optimized out>, signal_id=<optimized out>, detail=<optimized out>) at ../gobject/gsignal.c:3597
    #15 0x00007ffff7025b78 in g_closure_invoke (closure=0x992740, return_value=0x0, n_param_values=1, param_values=0x7fffffffcf30, invocation_hint=0x7fffffffce80)
    at ../gobject/gclosure.c:833
    #16 0x00007ffff7043fba in signal_emit_unlocked_R
    (node=node@entry=0x7fffffffd020, detail=detail@entry=0, instance=instance@entry=0x628360, emission_return=emission_return@entry=0x0, instance_and_params=instance_and_params@entry=0x7fffffffcf30) at ../gobject/gsignal.c:3902
    #17 0x00007ffff7045fcc in signal_emit_valist_unlocked (instance=instance@entry=0x628360, signal_id=signal_id@entry=244, detail=detail@entry=0, var_args=var_args@entry=0x7fffffffd180)
    at ../gobject/gsignal.c:3534
    #18 0x00007ffff7046248 in g_signal_emit_valist (instance=0x628360, signal_id=244, detail=0, var_args=var_args@entry=0x7fffffffd180) at ../gobject/gsignal.c:3277
#20 0x00007ffff7800911 in _gdk_frame_clock_emit_layout (frame_clock=0x628360) at ../gdk/gdkframeclock.c:723
#21 0x00007ffff7801ac1 in gdk_frame_clock_paint_idle (data=0x628360) at ../gdk/gdkframeclockidle.c:610
#22 0x00007ffff780167d in gdk_frame_clock_flush_idle (data=0x628360) at ../gdk/gdkframeclockidle.c:400
#23 0x00007ffff70c4769 in g_timeout_dispatch (source=0x1ecd930, callback=0x7ffff780157b <gdk_frame_clock_flush_idle>, user_data=0x628360) at ../glib/gmain.c:5111
#24 0x00007ffff70be5e0 in g_main_dispatch (context=0x445370) at ../glib/gmain.c:3398
#25 g_main_context_dispatch_unlocked (context=0x445370) at ../glib/gmain.c:4249
#26 0x00007ffff70c7708 in g_main_context_iterate_unlocked (context=context@entry=0x445370, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at ../glib/gmain.c:4314
#27 0x00007ffff70c78b7 in g_main_context_iteration (context=context@entry=0x445370, may_block=may_block@entry=1) at ../glib/gmain.c:4379
#28 0x00007ffff6f031ed in g_application_run (application=0x442150, argc=<optimized out>, argv=<optimized out>) at ../gio/gapplication.c:2715
#29 0x00000000004094a5 in main (argc=1, argv=0x7fffffffd6a8) at ../demos/node-editor/main.c:27