diff --git a/app/dialogs/preferences-dialog.c b/app/dialogs/preferences-dialog.c
index 7507156d43..137e19665c 100644
--- a/app/dialogs/preferences-dialog.c
+++ b/app/dialogs/preferences-dialog.c
@@ -90,6 +90,7 @@ static GtkWidget * prefs_dialog_new                (Gimp       *gimp,
 static void        prefs_response                  (GtkWidget  *widget,
                                                     gint        response_id,
                                                     GtkWidget  *dialog);
+static void        prefs_box_style_updated         (GtkWidget  *widget);
 
 static void   prefs_color_management_reset         (GtkWidget    *widget,
                                                     GObject      *config);
@@ -391,6 +392,14 @@ prefs_response (GtkWidget *widget,
   gtk_widget_destroy (dialog);
 }
 
+static void
+prefs_box_style_updated (GtkWidget *widget)
+{
+  GimpPrefsBox *box = GIMP_PREFS_BOX (widget);
+
+  GTK_WIDGET_GET_CLASS (box)->style_updated (GTK_WIDGET (box));
+}
+
 static void
 prefs_color_management_reset (GtkWidget *widget,
                               GObject   *config)
@@ -1193,6 +1202,16 @@ prefs_dialog_new (Gimp       *gimp,
 
   g_object_set_data (G_OBJECT (dialog), "prefs-box", prefs_box);
 
+  /* Notify the prefs box to update its tree icon sizes
+   * based on user preferences */
+  g_signal_connect_object (config,
+                           "notify::override-theme-icon-size",
+                           G_CALLBACK (prefs_box_style_updated),
+                           prefs_box, G_CONNECT_AFTER | G_CONNECT_SWAPPED);
+  g_signal_connect_object (config,
+                           "notify::custom-icon-size",
+                           G_CALLBACK (prefs_box_style_updated),
+                           prefs_box, G_CONNECT_AFTER | G_CONNECT_SWAPPED);
 
   /**********************/
   /*  System Resources  */
diff --git a/app/gui/themes.c b/app/gui/themes.c
index 23c1572a74..91d5ec8abb 100644
--- a/app/gui/themes.c
+++ b/app/gui/themes.c
@@ -484,6 +484,8 @@ themes_apply_theme (Gimp          *gimp,
             "\n"
             "* { -GimpColorNotebook-tab-icon-size: %s; }"
             "\n"
+            "* { -GimpPrefsBox-tab-icon-size: %s; }"
+            "\n"
             "* { -GimpEditor-button-icon-size: %s; }"
             "\n"
             "* { -GimpDisplayShell-button-icon-size: %s; }"
@@ -496,8 +498,8 @@ themes_apply_theme (Gimp          *gimp,
             "\n"
             "paned separator { padding: %dpx; }",
             tool_icon_size, tool_icon_size, tab_icon_size, tab_icon_size,
-            button_icon_size, button_icon_size, tool_icon_size, pal_padding,
-            tab_padding, sep_padding);
+            tab_icon_size, button_icon_size, button_icon_size, tool_icon_size,
+            pal_padding, tab_padding, sep_padding);
         }
 
       if (! error && config->font_relative_size != 1.0)
diff --git a/app/widgets/gimpprefsbox.c b/app/widgets/gimpprefsbox.c
index dafd5d7a06..d3217d1307 100644
--- a/app/widgets/gimpprefsbox.c
+++ b/app/widgets/gimpprefsbox.c
@@ -64,7 +64,13 @@ struct _GimpPrefsBoxPrivate
 #define GET_PRIVATE(obj) (((GimpPrefsBox *) (obj))->priv)
 
 
-static void   gimp_prefs_box_finalize             (GObject          *object);
+static void      gimp_prefs_box_finalize              (GObject      *object);
+
+static void      gimp_prefs_box_style_updated         (GtkWidget    *widget);
+static gboolean  gimp_prefs_box_style_updated_foreach (GtkTreeModel *model,
+                                                       GtkTreePath  *path,
+                                                       GtkTreeIter  *iter,
+                                                       gpointer      data);
 
 static void   gimp_prefs_box_tree_select_callback (GtkTreeSelection *sel,
                                                    GimpPrefsBox     *box);
@@ -78,9 +84,21 @@ G_DEFINE_TYPE_WITH_PRIVATE (GimpPrefsBox, gimp_prefs_box, GTK_TYPE_BOX)
 static void
 gimp_prefs_box_class_init (GimpPrefsBoxClass *klass)
 {
-  GObjectClass *object_class = G_OBJECT_CLASS (klass);
+  GObjectClass   *object_class = G_OBJECT_CLASS (klass);
+  GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (klass);
 
   object_class->finalize = gimp_prefs_box_finalize;
+
+  widget_class->style_updated = gimp_prefs_box_style_updated;
+
+  gtk_widget_class_install_style_property (widget_class,
+                                           g_param_spec_enum ("tab-icon-size",
+                                                              NULL, NULL,
+                                                              GTK_TYPE_ICON_SIZE,
+                                                              GTK_ICON_SIZE_BUTTON,
+                                                              G_PARAM_READABLE));
+
+  gtk_widget_class_set_css_name (widget_class, "GimpPrefsBox");
 }
 
 static void
@@ -90,6 +108,7 @@ gimp_prefs_box_init (GimpPrefsBox *box)
   GtkTreeViewColumn   *column;
   GtkCellRenderer     *cell;
   GtkTreeSelection    *sel;
+  GtkIconSize          tab_icon_size;
   GtkWidget           *frame;
   GtkWidget           *hbox;
   GtkWidget           *vbox;
@@ -98,7 +117,11 @@ gimp_prefs_box_init (GimpPrefsBox *box)
 
   private = box->priv;
 
-  private->tree_icon_size = GTK_ICON_SIZE_BUTTON;
+  gtk_widget_style_get (GTK_WIDGET (box),
+                        "tab-icon-size", &tab_icon_size,
+                        NULL);
+
+  private->tree_icon_size = tab_icon_size;
   private->page_icon_size = GTK_ICON_SIZE_DIALOG;
 
   gtk_orientable_set_orientation (GTK_ORIENTABLE (box),
@@ -208,6 +231,37 @@ gimp_prefs_box_finalize (GObject *object)
   G_OBJECT_CLASS (parent_class)->finalize (object);
 }
 
+static void
+gimp_prefs_box_style_updated (GtkWidget *widget)
+{
+  GTK_WIDGET_CLASS (parent_class)->style_updated (widget);
+
+  if (GET_PRIVATE (widget)->store)
+    gtk_tree_model_foreach (GTK_TREE_MODEL (GET_PRIVATE (widget)->store),
+                            gimp_prefs_box_style_updated_foreach,
+                            widget);
+}
+
+static gboolean
+gimp_prefs_box_style_updated_foreach (GtkTreeModel *model,
+                                      GtkTreePath  *path,
+                                      GtkTreeIter  *iter,
+                                      gpointer      data)
+{
+  GimpPrefsBox *box = GIMP_PREFS_BOX (data);
+  GtkIconSize   tab_icon_size;
+
+  gtk_widget_style_get (GTK_WIDGET (box),
+                        "tab-icon-size", &tab_icon_size,
+                        NULL);
+
+  gtk_tree_store_set (GTK_TREE_STORE (model), iter,
+                      COLUMN_TREE_ICON_SIZE, tab_icon_size,
+                      -1);
+
+  return FALSE;
+}
+
 static void
 gimp_prefs_box_tree_select_callback (GtkTreeSelection *sel,
                                      GimpPrefsBox     *box)