UI: Set modifier panel expansion on every redraw

This will fix situations where the modifier epansion was set elsewhere
besides the UI, like from the python console, solving the drawing part
of T77502.

Also adds  update tags to the show_expanded property, which means
the properties window redraws when the property changes.

1 files changed, 1 insertions, 0 deletions

diff --git a/source/blender/makesrna/intern/rna_modifier.c b/source/blender/makesrna/intern/rna_modifier.c
index a0026797c68..92eec6190da 100644
--- a/source/blender/makesrna/intern/rna_modifier.c
+++ b/source/blender/makesrna/intern/rna_modifier.c
@@ -6877,6 +6877,7 @@ void RNA_def_modifier(BlenderRNA *brna)
   RNA_def_property_override_flag(prop, PROPOVERRIDE_OVERRIDABLE_LIBRARY);
   RNA_def_property_ui_text(prop, "Expanded", "Set modifier expanded in the user interface");
   RNA_def_property_ui_icon(prop, ICON_DISCLOSURE_TRI_RIGHT, 1);
+  RNA_def_property_update(prop, NC_OBJECT | ND_MODIFIER, NULL);
 
   prop = RNA_def_property(srna, "use_apply_on_spline", PROP_BOOLEAN, PROP_NONE);
   RNA_def_property_boolean_sdna(prop, NULL, "mode", eModifierMode_ApplyOnSpline);