diff --git a/lib/Slic3r/GUI/Plater/ObjectSettingsDialog.pm b/lib/Slic3r/GUI/Plater/ObjectSettingsDialog.pm
index b97207c39..22d2f4ee4 100644
--- a/lib/Slic3r/GUI/Plater/ObjectSettingsDialog.pm
+++ b/lib/Slic3r/GUI/Plater/ObjectSettingsDialog.pm
@@ -132,7 +132,7 @@ sub update_optgroup {
                 my ($opt_key) = @{$line->{options}};  # we assume that we have one option per line
                 my $btn = Wx::BitmapButton->new($self, -1, Wx::Bitmap->new("$Slic3r::var/delete.png", wxBITMAP_TYPE_PNG));
                 EVT_BUTTON($self, $btn, sub {
-                    delete $self->model_object->config->{$opt_key};
+                    $self->model_object->config->erase($opt_key);
                     Slic3r::GUI->CallAfter(sub { $self->update_optgroup });
                 });
                 return $btn;
diff --git a/xs/src/Config.cpp b/xs/src/Config.cpp
index 20be9a3c2..b2783e357 100644
--- a/xs/src/Config.cpp
+++ b/xs/src/Config.cpp
@@ -289,6 +289,11 @@ DynamicConfig::keys(t_config_option_keys *keys) {
         keys->push_back(it->first);
 }
 
+void
+DynamicConfig::erase(const t_config_option_key opt_key) {
+    this->options.erase(opt_key);
+}
+
 void
 StaticConfig::keys(t_config_option_keys *keys) {
     for (t_optiondef_map::const_iterator it = this->def->begin(); it != this->def->end(); ++it) {
diff --git a/xs/src/Config.hpp b/xs/src/Config.hpp
index 71f945349..0e68437f4 100644
--- a/xs/src/Config.hpp
+++ b/xs/src/Config.hpp
@@ -430,6 +430,7 @@ class DynamicConfig : public ConfigBase
     ~DynamicConfig();
     ConfigOption* option(const t_config_option_key opt_key, bool create = false);
     void keys(t_config_option_keys *keys);
+    void erase(const t_config_option_key opt_key);
     
     private:
     DynamicConfig(const DynamicConfig& other);              // we disable this by making it private and unimplemented
diff --git a/xs/xsp/Config.xsp b/xs/xsp/Config.xsp
index 461f1cd89..3e1b07cd4 100644
--- a/xs/xsp/Config.xsp
+++ b/xs/xsp/Config.xsp
@@ -24,6 +24,7 @@
         %code{% THIS->apply(*other, true); %};
     std::vector<std::string> get_keys()
         %code{% THIS->keys(&RETVAL); %};
+    void erase(t_config_option_key opt_key);
 };
 
 %name{Slic3r::Config::Print} class PrintConfig {