diff -r 3ee18a3a0f58 -r 772ff096a326 plover-gtk/stockicons.c
--- a/plover-gtk/stockicons.c	Mon Nov 02 19:01:50 2015 +0000
+++ b/plover-gtk/stockicons.c	Fri Jul 08 08:33:44 2016 +0100
@@ -34,6 +34,8 @@
     GSList *tmp_list;
     static gint found_svg=-1;
     gchar **mime_types,**mime_type;
+    if (g_getenv("PLOVER_IGNORE_SVG_SUPPORT"))
+	return FALSE;
     if (found_svg!=-1)
 	return found_svg;
     formats=gdk_pixbuf_get_formats();
@@ -55,10 +57,15 @@
 {
     int w,h;
     GdkPixbuf *pixbuf;
+    GtkSettings *settings;
     GtkIconSource *source;
-    if (gtk_icon_size_lookup(size,&w,&h))
+    GError *err=NULL;
+    settings=gtk_settings_get_default();
+    if (!settings)
+	g_warning("plover: Can't add icons without a default screen");
+    else if (gtk_icon_size_lookup_for_settings(settings,size,&w,&h))
     {
-	pixbuf=gdk_pixbuf_new_from_file_at_size(filename,w,h,NULL);
+	pixbuf=gdk_pixbuf_new_from_file_at_size(filename,w,h,&err);
 	if (pixbuf)
 	{
 	    source=gtk_icon_source_new();
@@ -69,6 +76,11 @@
 	    gtk_icon_source_free(source);
 	    g_object_unref(pixbuf);
 	}
+	else
+	{
+	    g_warning("%s: %s",filename,err->message);
+	    g_error_free(err);
+	}
     }
 }
 
@@ -87,23 +99,30 @@
  */
 void plover_icons_add_to_stock(const char *type,const char *name)
 {
-    gchar *prefix,*s,*filename;
+    gchar *datadir,*prefix,*s,*filename;
     GtkIconSource *source;
     GtkIconSet *icon_set;
     GtkIconFactory *factory;
     factory=gtk_icon_factory_new();
     icon_set=gtk_icon_set_new();
+    datadir=g_strdup(g_getenv("PLOVER_ICONS_DATADIR"));
+    if (!datadir)
+    {
 #ifdef WIN32
-    prefix=g_win32_get_package_installation_directory_of_module(NULL);
+	prefix=g_win32_get_package_installation_directory_of_module(NULL);
 #else
-    prefix=NULL;
+	prefix=NULL;
 #endif
+	if (!prefix)
+	    prefix=g_strdup("/usr");
+	datadir=g_strconcat(prefix,"share",NULL);
+	g_free(prefix);
+    }
     if (plover_pixbuf_supports_svg())
     {
 	source=gtk_icon_source_new();
 	s=g_strconcat(name,".svg",NULL);
-	filename=g_build_filename(prefix?prefix:"/usr",
-	  "share/icons/hicolor/scalable",type,s,NULL);
+	filename=g_build_filename(datadir,"icons/hicolor/scalable",type,s,NULL);
 	g_free(s);
 	gtk_icon_source_set_filename(source,filename);
 	g_free(filename);
@@ -113,8 +132,7 @@
     else
     {
 	s=g_strconcat(name,".png",NULL);
-	filename=g_build_filename(prefix?prefix:"/usr",
-	  "share/icons/hicolor/24x24",type,s,NULL);
+	filename=g_build_filename(datadir,"icons/hicolor/24x24",type,s,NULL);
 	plover_install_icon_at_size(name,icon_set,GTK_ICON_SIZE_MENU,
 	  filename);
 	plover_install_icon_at_size(name,icon_set,GTK_ICON_SIZE_BUTTON,
@@ -124,8 +142,7 @@
 	plover_install_icon_at_size(name,icon_set,GTK_ICON_SIZE_LARGE_TOOLBAR,
 	  filename);
 	g_free(filename);
-	filename=g_build_filename(prefix?prefix:"/usr",
-	  "share/icons/hicolor/48x48",type,s,NULL);
+	filename=g_build_filename(datadir,"icons/hicolor/48x48",type,s,NULL);
 	plover_install_icon_at_size(name,icon_set,GTK_ICON_SIZE_DND,
 	  filename);
 	plover_install_icon_at_size(name,icon_set,GTK_ICON_SIZE_DIALOG,
@@ -133,6 +150,7 @@
 	g_free(filename);
 	g_free(s);
     }
+    g_free(datadir);
     gtk_icon_factory_add(factory,name,icon_set);
     gtk_icon_set_unref(icon_set);
     //icon_set=gtk_icon_factory_lookup(factory,name);