diff --git a/release/datafiles/userdef/userdef_default_theme.c b/release/datafiles/userdef/userdef_default_theme.c
index 897a566cceb..736fa8dff95 100644
--- a/release/datafiles/userdef/userdef_default_theme.c
+++ b/release/datafiles/userdef/userdef_default_theme.c
@@ -239,8 +239,8 @@ const bTheme U_theme_default = {
       .blend = 0.5f,
     },
     .widget_emboss = RGBA(0x00000026),
-    .menu_shadow_fac = 0.4f,
-    .menu_shadow_width = 2,
+    .menu_shadow_fac = 0.2f,
+    .menu_shadow_width = 6,
     .editor_border = RGBA(0x161616ff),
     .editor_outline = RGBA(0xffffff15),
     .editor_outline_active = RGBA(0xffffff2a),
diff --git a/source/blender/blenkernel/BKE_blender_version.h b/source/blender/blenkernel/BKE_blender_version.h
index 297e710d660..1fbee3e2be6 100644
--- a/source/blender/blenkernel/BKE_blender_version.h
+++ b/source/blender/blenkernel/BKE_blender_version.h
@@ -27,7 +27,7 @@
 
 /* Blender file format version. */
 #define BLENDER_FILE_VERSION BLENDER_VERSION
-#define BLENDER_FILE_SUBVERSION 18
+#define BLENDER_FILE_SUBVERSION 19
 
 /* Minimum Blender version that supports reading file written with the current
  * version. Older Blender versions will test this and cancel loading the file, showing a warning to
diff --git a/source/blender/blenloader/intern/versioning_userdef.cc b/source/blender/blenloader/intern/versioning_userdef.cc
index 613969e72ec..dcadffb5b8c 100644
--- a/source/blender/blenloader/intern/versioning_userdef.cc
+++ b/source/blender/blenloader/intern/versioning_userdef.cc
@@ -326,6 +326,11 @@ static void do_versions_theme(const UserDef *userdef, bTheme *btheme)
     FROM_DEFAULT_V4_UCHAR(space_preferences.button);
   }
 
+  if (!USER_VERSION_ATLEAST(500, 19)) {
+    btheme->tui.menu_shadow_fac = U_theme_default.tui.menu_shadow_fac;
+    btheme->tui.menu_shadow_width = U_theme_default.tui.menu_shadow_width;
+  }
+
   /**
    * Always bump subversion in BKE_blender_version.h when adding versioning
    * code here, and wrap it inside a USER_VERSION_ATLEAST check.
diff --git a/source/blender/editors/interface/interface_panel.cc b/source/blender/editors/interface/interface_panel.cc
index f82169c6693..6a29c0d0cc0 100644
--- a/source/blender/editors/interface/interface_panel.cc
+++ b/source/blender/editors/interface/interface_panel.cc
@@ -1233,6 +1233,21 @@ void ui_draw_layout_panels_backdrop(const ARegion *region,
   }
 }
 
+static void panel_draw_softshadow(const rctf *box_rect,
+                                  const int roundboxalign,
+                                  const float radius,
+                                  const float shadow_width)
+{
+  const float outline = U.pixelsize;
+
+  rctf shadow_rect = *box_rect;
+  BLI_rctf_pad(&shadow_rect, -outline, -outline);
+  UI_draw_roundbox_corner_set(roundboxalign);
+
+  const float shadow_alpha = UI_GetTheme()->tui.menu_shadow_fac;
+  ui_draw_dropshadow(&shadow_rect, radius, shadow_width, 1.0f, shadow_alpha);
+}
+
 static void panel_draw_aligned_backdrop(const ARegion *region,
                                         const Panel *panel,
                                         const rcti *rect,
@@ -1241,6 +1256,7 @@ static void panel_draw_aligned_backdrop(const ARegion *region,
   const bool is_open = !UI_panel_is_closed(panel);
   const bool is_subpanel = panel->type->parent != nullptr;
   const bool has_header = (panel->type->flag & PANEL_TYPE_NO_HEADER) == 0;
+  const bool is_dragging = UI_panel_is_dragging(panel);
 
   if (is_subpanel && !is_open) {
     return;
@@ -1253,6 +1269,22 @@ static void panel_draw_aligned_backdrop(const ARegion *region,
   immBindBuiltinProgram(GPU_SHADER_3D_UNIFORM_COLOR);
   GPU_blend(GPU_BLEND_ALPHA);
 
+  /* Draw shadow on top-level panels with headers during drag or region overlap. */
+  if (!is_subpanel && has_header && (region->overlap || is_dragging)) {
+    /* Make shadow wider (at least 16px) while the panel is being dragged. */
+    const float shadow_width = is_dragging ?
+                                   max_ii(int(16.0f * UI_SCALE_FAC), UI_ThemeMenuShadowWidth()) :
+                                   UI_ThemeMenuShadowWidth();
+    const int roundboxalign = is_open ? UI_CNR_BOTTOM_RIGHT | UI_CNR_BOTTOM_LEFT : UI_CNR_ALL;
+
+    rctf box_rect;
+    box_rect.xmin = rect->xmin;
+    box_rect.xmax = rect->xmax;
+    box_rect.ymin = is_open ? rect->ymin : header_rect->ymin;
+    box_rect.ymax = header_rect->ymax;
+    panel_draw_softshadow(&box_rect, roundboxalign, radius, shadow_width);
+  }
+
   /* Panel backdrop. */
   if (is_open || !has_header) {
     float panel_backcolor[4];
diff --git a/source/blender/makesrna/intern/rna_userdef.cc b/source/blender/makesrna/intern/rna_userdef.cc
index ff97e8629d7..8e6a8f07770 100644
--- a/source/blender/makesrna/intern/rna_userdef.cc
+++ b/source/blender/makesrna/intern/rna_userdef.cc
@@ -1912,13 +1912,14 @@ static void rna_def_userdef_theme_ui(BlenderRNA *brna)
   RNA_def_property_update(prop, 0, "rna_userdef_theme_update");
 
   prop = RNA_def_property(srna, "menu_shadow_fac", PROP_FLOAT, PROP_FACTOR);
-  RNA_def_property_ui_text(prop, "Menu Shadow Strength", "Blending factor for menu shadows");
+  RNA_def_property_ui_text(
+      prop, "Panel/Menu Shadow Strength", "Blending factor for panel and menu shadows");
   RNA_def_property_range(prop, 0.01f, 1.0f);
   RNA_def_property_update(prop, 0, "rna_userdef_theme_update");
 
   prop = RNA_def_property(srna, "menu_shadow_width", PROP_INT, PROP_PIXEL);
   RNA_def_property_ui_text(
-      prop, "Menu Shadow Width", "Width of menu shadows, set to zero to disable");
+      prop, "Panel/Menu Shadow Width", "Width of panel and menu shadows, set to zero to disable");
   RNA_def_property_range(prop, 0.0f, 24.0f);
   RNA_def_property_update(prop, 0, "rna_userdef_theme_update");