Hi,

I was playing with themes today and noticed that themes which replaced icons successfully in GIMP 2.8 don't anymore in master.
I could bisect the problem from this commit:

--------------------------------------------------------
commit 9cb81db026da7a1f150718a7e5f6feb0fdc9f7e8
Author: Michael Natterer <mitch@gimp.org>
Date:   Thu May 8 19:00:18 2014 +0200

    app: actually use named icons for the toolbox icons

diff --git a/app/widgets/gimptoolpalette.c b/app/widgets/gimptoolpalette.c
index 05e9d7e..a1195dc 100644
--- a/app/widgets/gimptoolpalette.c
+++ b/app/widgets/gimptoolpalette.c
@@ -396,7 +396,8 @@ gimp_tool_palette_initialize_tools (GimpToolPalette *palette)
 
       icon_name = gimp_viewable_get_icon_name (GIMP_VIEWABLE (tool_info));
 
-      item = gtk_radio_tool_button_new_from_stock (item_group, icon_name);
+      item = gtk_radio_tool_button_new (item_group);
+      gtk_tool_button_set_icon_name (GTK_TOOL_BUTTON (item), icon_name);
       item_group = gtk_radio_tool_button_get_group (GTK_RADIO_TOOL_BUTTON (item));
       gtk_tool_item_group_insert (GTK_TOOL_ITEM_GROUP (group), item, -1);
       gtk_widget_show (GTK_WIDGET (item));
--------------------------------------------------------

Well reverting this don't fully fix the problem, but at least it does fix it in the toolbox (other icons though still don't show, I imagine similar commits to this one, still to be found, may be the cause).

From what I understand, this may be normal (?), like new code don't use "stock icons", but "named icon", but honestly I don't understand the difference of both concepts.

And in any case, it means that working themes in GIMP 2.8 won't work in GIMP 2.10.
So is it considered normal? If so, what is the new way to make a theme with custom icons in GIMP 2.10? I searched for good generic GTK+ tutorial but could not find anything usable for GIMP master.
Or is it not normal and should the above commit be reverted?
Thanks.