Fix of

https://github.com/prusa3d/Slic3r/issues/1142
https://github.com/prusa3d/Slic3r/issues/1257
The preset keys not belonging into the config group are removed
and the problem is reported into the boost::log

xs/src/libslic3r/Config.hpp

@@ -1171,6 +1171,7 @@ public:
     // Allow DynamicConfig to be instantiated on ints own without a definition.
     // If the definition is not defined, the method requiring the definition will throw NoDefinitionException.
     const ConfigDef*        def() const override { return nullptr; };
+    bool                    has(const t_config_option_key &opt_key) const { return this->options.find(opt_key) != this->options.end(); }
     template<class T> T*    opt(const t_config_option_key &opt_key, bool create = false)
         { return dynamic_cast<T*>(this->option(opt_key, create)); }
     template<class T> const T* opt(const t_config_option_key &opt_key) const
@@ -1214,7 +1215,7 @@ public:
     bool                opt_bool(const t_config_option_key &opt_key) const                      { return this->option<ConfigOptionBool>(opt_key)->value != 0; }
     bool                opt_bool(const t_config_option_key &opt_key, unsigned int idx) const    { return this->option<ConfigOptionBools>(opt_key)->get_at(idx) != 0; }
 
-private:
+protected:
     typedef std::map<t_config_option_key,ConfigOption*> t_options_map;
     t_options_map options;
 };

xs/src/libslic3r/PrintConfig.cpp

@@ -1,6 +1,7 @@
 #include "PrintConfig.hpp"
 #include "I18N.hpp"
 
+#include <algorithm>
 #include <set>
 #include <boost/algorithm/string/replace.hpp>
 #include <boost/algorithm/string/case_conv.hpp>
@@ -2241,6 +2242,25 @@ std::string DynamicPrintConfig::validate()
     return fpc.validate();
 }
 
+size_t DynamicPrintConfig::remove_keys_not_in(const DynamicPrintConfig &default_config, std::string &removed_keys_message)
+{
+    size_t n_removed_keys = 0;
+    for (const auto &kvp : this->options) {
+        const std::string &key = kvp.first;
+        if (! default_config.has(key)) {
+            if (removed_keys_message.empty())
+                removed_keys_message = key;
+            else {
+                removed_keys_message += ", ";
+                removed_keys_message += key;
+            }
+            this->erase(key);
+            ++ n_removed_keys;
+        }
+    }
+    return n_removed_keys;
+}
+
 double PrintConfig::min_object_distance() const
 {
     return PrintConfig::min_object_distance(static_cast<const ConfigBase*>(this));

xs/src/libslic3r/PrintConfig.hpp

@@ -168,6 +168,10 @@ public:
     // Validate the PrintConfig. Returns an empty string on success, otherwise an error message is returned.
     std::string         validate();
 
+    // Remove all keys not in "valid_keys", return number of removed keys and add the list of keys to "removed_keys_message.
+    // valid_keys has to be sorted lexicographically.
+    size_t              remove_keys_not_in(const DynamicPrintConfig &default_config, std::string &removed_keys_message);
+
     // Verify whether the opt_key has not been obsoleted or renamed.
     // Both opt_key and value may be modified by handle_legacy().
     // If the opt_key is no more valid in this version of Slic3r, opt_key is cleared by handle_legacy().

xs/src/slic3r/GUI/Preset.cpp

@@ -417,7 +417,14 @@ void PresetCollection::load_presets(const std::string &dir_path, const std::stri
             try {
                 Preset preset(m_type, name, false);
                 preset.file = dir_entry.path().string();
-                preset.load(keys);
+                DynamicPrintConfig &config = preset.load(keys);
+                // Report configuration fields, which are misplaced into a wrong group.
+                std::string incorrect_keys;
+                if (config.remove_keys_not_in(this->default_preset().config, incorrect_keys) > 0)
+                    BOOST_LOG_TRIVIAL(error) << "Error in \"" << dir_entry.path().string() << "\": The preset contains the following incorrect keys: " << 
+                        incorrect_keys << ", which were ignored";
+                // Normalize once again to set the length of the filament specific vectors to 1.
+                Preset::normalize(config);
                 m_presets.emplace_back(preset);
             } catch (const std::runtime_error &err) {
                 errors_cummulative += err.what();

xs/src/slic3r/GUI/PresetBundle.cpp

@@ -919,24 +919,12 @@ size_t PresetBundle::load_configbundle(const std::string &path, unsigned int fla
             DynamicPrintConfig config(default_config);
             for (auto &kvp : section.second)
                 config.set_deserialize(kvp.first, kvp.second.data());
-            Preset::normalize(config);
             // Report configuration fields, which are misplaced into a wrong group.
             std::string incorrect_keys;
-            size_t      n_incorrect_keys = 0;
+            if (config.remove_keys_not_in(default_config, incorrect_keys) > 0)
-            for (const std::string &key : config.keys())
-                if (! default_config.has(key)) {
-                    if (incorrect_keys.empty())
-                        incorrect_keys = key;
-                    else {
-                        incorrect_keys += ", ";
-                        incorrect_keys += key;
-                    }
-                    config.erase(key);
-                    ++ n_incorrect_keys;
-                }
-            if (! incorrect_keys.empty())
                 BOOST_LOG_TRIVIAL(error) << "Error in a Vendor Config Bundle \"" << path << "\": The printer preset \"" << 
                     section.first << "\" contains the following incorrect keys: " << incorrect_keys << ", which were removed";            
+            Preset::normalize(config);
             if ((flags & LOAD_CFGBNDLE_SYSTEM) && presets == &printers) {
                 // Filter out printer presets, which are not mentioned in the vendor profile.
                 // These presets are considered not installed.