diff --git a/Core/GDCore/Events/Parsers/ExpressionParser2.cpp b/Core/GDCore/Events/Parsers/ExpressionParser2.cpp
index cf71b9abd3..e943398781 100644
--- a/Core/GDCore/Events/Parsers/ExpressionParser2.cpp
+++ b/Core/GDCore/Events/Parsers/ExpressionParser2.cpp
@@ -19,8 +19,10 @@
 #include "GDCore/Project/Project.h"
 #include "GDCore/Tools/Localization.h"
 #include "GDCore/Tools/MakeUnique.h"
+#include "GrammarTerminals.h"
 
 using namespace std;
+using namespace gd::GrammarTerminals;
 
 namespace gd {
 
diff --git a/Core/GDCore/Events/Parsers/ExpressionParser2.h b/Core/GDCore/Events/Parsers/ExpressionParser2.h
index 6f2058ed99..782b274f15 100644
--- a/Core/GDCore/Events/Parsers/ExpressionParser2.h
+++ b/Core/GDCore/Events/Parsers/ExpressionParser2.h
@@ -18,6 +18,7 @@
 #include "GDCore/String.h"
 #include "GDCore/Tools/Localization.h"
 #include "GDCore/Tools/MakeUnique.h"
+#include "GrammarTerminals.h"
 namespace gd {
 class Expression;
 class ObjectsContainer;
@@ -28,6 +29,8 @@ class ExpressionMetadata;
 
 namespace gd {
 
+using namespace gd::GrammarTerminals;
+
 /** \brief Parse an expression, returning a tree of node corresponding
  * to the parsed expression.
  *
@@ -211,7 +214,7 @@ class GD_CORE_API ExpressionParser2 {
       }
       SkipIfChar(IsClosingParenthesis);
       return factor;
-    } else if (IsIdentifierAllowedChar()) {
+    } else if (CheckIfChar(IsAllowedInIdentifier)) {
       return Identifier();
     }
 
@@ -606,95 +609,6 @@ class GD_CORE_API ExpressionParser2 {
     return predicate(character);
   }
 
-  bool IsIdentifierAllowedChar() {
-    if (currentPosition >= expression.size()) return false;
-    gd::String::value_type character = expression[currentPosition];
-
-    // Quickly compare if the character is a number or ASCII character.
-    if ((character >= '0' && character <= '9') ||
-        (character >= 'A' && character <= 'Z') ||
-        (character >= 'a' && character <= 'z'))
-      return true;
-
-    // Otherwise do the full check against separators forbidden in identifiers.
-    if (!IsParameterSeparator(character) && !IsDot(character) &&
-        !IsQuote(character) && !IsBracket(character) &&
-        !IsExpressionOperator(character) && !IsTermOperator(character)) {
-      return true;
-    }
-
-    return false;
-  }
-
-  static bool IsWhitespace(gd::String::value_type character) {
-    return character == ' ' || character == '\n' || character == '\r';
-  }
-
-  static bool IsParameterSeparator(gd::String::value_type character) {
-    return character == ',';
-  }
-
-  static bool IsDot(gd::String::value_type character) {
-    return character == '.';
-  }
-
-  static bool IsQuote(gd::String::value_type character) {
-    return character == '"';
-  }
-
-  static bool IsBracket(gd::String::value_type character) {
-    return character == '(' || character == ')' || character == '[' ||
-           character == ']' || character == '{' || character == '}';
-  }
-
-  static bool IsOpeningParenthesis(gd::String::value_type character) {
-    return character == '(';
-  }
-
-  static bool IsClosingParenthesis(gd::String::value_type character) {
-    return character == ')';
-  }
-
-  static bool IsOpeningSquareBracket(gd::String::value_type character) {
-    return character == '[';
-  }
-
-  static bool IsClosingSquareBracket(gd::String::value_type character) {
-    return character == ']';
-  }
-
-  static bool IsExpressionEndingChar(gd::String::value_type character) {
-    return character == ',' || IsClosingParenthesis(character) ||
-           IsClosingSquareBracket(character);
-  }
-
-  static bool IsExpressionOperator(gd::String::value_type character) {
-    return character == '+' || character == '-' || character == '<' ||
-           character == '>' || character == '?' || character == '^' ||
-           character == '=' || character == '\\' || character == ':' ||
-           character == '!';
-  }
-
-  static bool IsUnaryOperator(gd::String::value_type character) {
-    return character == '+' || character == '-';
-  }
-
-  static bool IsTermOperator(gd::String::value_type character) {
-    return character == '/' || character == '*';
-  }
-
-  static bool IsNumberFirstChar(gd::String::value_type character) {
-    return character == '.' || (character >= '0' && character <= '9');
-  }
-
-  static bool IsNonZeroDigit(gd::String::value_type character) {
-    return (character >= '1' && character <= '9');
-  }
-
-  static bool IsZeroDigit(gd::String::value_type character) {
-    return character == '0';
-  }
-
   bool IsNamespaceSeparator() {
     // Namespace separator is a special kind of delimiter as it is 2 characters
     // long
@@ -715,7 +629,7 @@ class GD_CORE_API ExpressionParser2 {
     gd::String name;
     size_t startPosition = currentPosition;
     while (currentPosition < expression.size() &&
-           (IsIdentifierAllowedChar()
+           (CheckIfChar(IsAllowedInIdentifier)
             // Allow whitespace in identifier name for compatibility
             || expression[currentPosition] == ' ')) {
       name += expression[currentPosition];
diff --git a/Core/GDCore/Events/Parsers/GrammarTerminals.h b/Core/GDCore/Events/Parsers/GrammarTerminals.h
new file mode 100644
index 0000000000..65c3c7e993
--- /dev/null
+++ b/Core/GDCore/Events/Parsers/GrammarTerminals.h
@@ -0,0 +1,107 @@
+#pragma once
+#include "GDCore/String.h"
+
+namespace gd {
+
+/**
+ * Contains functions to handle the grammar of the expressions accepted by GDevelop.
+ */
+namespace GrammarTerminals {
+
+inline bool IsWhitespace(gd::String::value_type character) {
+  return character == ' ' || character == '\n' || character == '\r';
+}
+
+inline bool IsParameterSeparator(gd::String::value_type character) {
+  return character == ',';
+}
+
+inline bool IsDot(gd::String::value_type character) { return character == '.'; }
+
+inline bool IsQuote(gd::String::value_type character) {
+  return character == '"';
+}
+
+inline bool IsBracket(gd::String::value_type character) {
+  return character == '(' || character == ')' || character == '[' ||
+         character == ']' || character == '{' || character == '}';
+}
+
+inline bool IsOpeningParenthesis(gd::String::value_type character) {
+  return character == '(';
+}
+
+inline bool IsClosingParenthesis(gd::String::value_type character) {
+  return character == ')';
+}
+
+inline bool IsOpeningSquareBracket(gd::String::value_type character) {
+  return character == '[';
+}
+
+inline bool IsClosingSquareBracket(gd::String::value_type character) {
+  return character == ']';
+}
+
+inline bool IsExpressionEndingChar(gd::String::value_type character) {
+  return character == ',' || IsClosingParenthesis(character) ||
+         IsClosingSquareBracket(character);
+}
+
+inline bool IsExpressionOperator(gd::String::value_type character) {
+  return character == '+' || character == '-' || character == '<' ||
+         character == '>' || character == '?' || character == '^' ||
+         character == '=' || character == '\\' || character == ':' ||
+         character == '!';
+}
+
+inline bool IsUnaryOperator(gd::String::value_type character) {
+  return character == '+' || character == '-';
+}
+
+inline bool IsTermOperator(gd::String::value_type character) {
+  return character == '/' || character == '*';
+}
+
+inline bool IsNumberFirstChar(gd::String::value_type character) {
+  return character == '.' || (character >= '0' && character <= '9');
+}
+
+inline bool IsNonZeroDigit(gd::String::value_type character) {
+  return (character >= '1' && character <= '9');
+}
+
+inline bool IsZeroDigit(gd::String::value_type character) {
+  return character == '0';
+}
+
+/**
+ * Check if the given character can be used in an identifier. This is
+ * any unicode character, except for:
+ * `, . " () [] {} + - < > ? ^ = \ : ! / *` and whitespaces (space, line break, carriage return).
+ *
+ * This is loosely based on what is allowed in languages like JavaScript
+ * (see https://mathiasbynens.be/notes/javascript-properties), without support
+ * for unicode escape syntax, and allowing all unicode ranges. The only
+ * disallowed characters are the one used for the grammar.
+ */
+inline bool IsAllowedInIdentifier(gd::String::value_type character) {
+  // Quickly compare if the character is a number or ASCII character.
+  if ((character >= '0' && character <= '9') ||
+      (character >= 'A' && character <= 'Z') ||
+      (character >= 'a' && character <= 'z'))
+    return true;
+
+  // Otherwise do the full check against separators forbidden in identifiers.
+  if (!IsParameterSeparator(character) && !IsDot(character) &&
+      !IsQuote(character) && !IsBracket(character) &&
+      !IsExpressionOperator(character) && !IsTermOperator(character) &&
+      !IsWhitespace(character)) {
+    return true;
+  }
+
+  return false;
+}
+
+}  // namespace GrammarTerminals
+}  // namespace gd
\ No newline at end of file
diff --git a/Core/GDCore/Project/Project.cpp b/Core/GDCore/Project/Project.cpp
index 2a55f8b9c1..d273df126e 100644
--- a/Core/GDCore/Project/Project.cpp
+++ b/Core/GDCore/Project/Project.cpp
@@ -15,6 +15,7 @@
 #include <vector>
 
 #include "GDCore/CommonTools.h"
+#include "GDCore/Events/Parsers/GrammarTerminals.h"
 #include "GDCore/Extensions/Metadata/ExpressionMetadata.h"
 #include "GDCore/Extensions/Metadata/MetadataProvider.h"
 #include "GDCore/Extensions/Platform.h"
@@ -49,6 +50,11 @@ using namespace std;
 
 namespace gd {
 
+// By default, disallow unicode in identifiers, but this can be set to true
+// by the IDE. In the future, this will be set to true by default, keeping backward compatibility.
+// We keep it disabled by default to progressively ask users to test it in real projects.
+bool Project::allowUsageOfUnicodeIdentifierNames = false;
+
 Project::Project()
     : name(_("Project")),
       version("1.0.0"),
@@ -630,8 +636,10 @@ void Project::UnserializeFrom(const SerializerElement& element) {
   SetAdaptGameResolutionAtRuntime(
       propElement.GetBoolAttribute("adaptGameResolutionAtRuntime", false));
   SetSizeOnStartupMode(propElement.GetStringAttribute("sizeOnStartupMode", ""));
-  SetAntialiasingMode(propElement.GetStringAttribute("antialiasingMode", "MSAA"));
-  SetAntialisingEnabledOnMobile(propElement.GetBoolAttribute("antialisingEnabledOnMobile", false));
+  SetAntialiasingMode(
+      propElement.GetStringAttribute("antialiasingMode", "MSAA"));
+  SetAntialisingEnabledOnMobile(
+      propElement.GetBoolAttribute("antialisingEnabledOnMobile", false));
   SetProjectUuid(propElement.GetStringAttribute("projectUuid", ""));
   SetAuthor(propElement.GetChild("author", 0, "Auteur").GetValue().GetString());
   SetPackageName(propElement.GetStringAttribute("packageName"));
@@ -887,7 +895,8 @@ void Project::SerializeTo(SerializerElement& element) const {
                            adaptGameResolutionAtRuntime);
   propElement.SetAttribute("sizeOnStartupMode", sizeOnStartupMode);
   propElement.SetAttribute("antialiasingMode", antialiasingMode);
-  propElement.SetAttribute("antialisingEnabledOnMobile", isAntialisingEnabledOnMobile);
+  propElement.SetAttribute("antialisingEnabledOnMobile",
+                           isAntialisingEnabledOnMobile);
   propElement.SetAttribute("projectUuid", projectUuid);
   propElement.SetAttribute("folderProject", folderProject);
   propElement.SetAttribute("packageName", packageName);
@@ -993,14 +1002,28 @@ void Project::SerializeTo(SerializerElement& element) const {
         externalSourceFilesElement.AddChild("sourceFile"));
 }
 
+void Project::AllowUsageOfUnicodeIdentifierNames(bool enable) {
+  allowUsageOfUnicodeIdentifierNames = enable;
+}
+
 bool Project::IsNameSafe(const gd::String& name) {
   if (name.empty()) return false;
 
   if (isdigit(name[0])) return false;
 
-  gd::String allowedCharacters =
-      "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_";
-  return !(name.find_first_not_of(allowedCharacters) != gd::String::npos);
+  if (!allowUsageOfUnicodeIdentifierNames) {
+    gd::String legacyAllowedCharacters =
+        "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_";
+    return !(name.find_first_not_of(legacyAllowedCharacters) != gd::String::npos);
+  } else {
+    for (auto character : name) {
+      if (!GrammarTerminals::IsAllowedInIdentifier(character)) {
+        return false;
+      }
+    }
+
+    return true;
+  }
 }
 
 gd::String Project::GetSafeName(const gd::String& name) {
@@ -1010,12 +1033,21 @@ gd::String Project::GetSafeName(const gd::String& name) {
 
   if (isdigit(name[0])) newName = "_" + newName;
 
-  gd::String allowedCharacters =
+  gd::String legacyAllowedCharacters =
       "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_";
-  
+
   for (size_t i = 0;i < newName.size();++i) {
+    // Note that iterating on the characters is not super efficient (O(n^2), which
+    // could be avoided with an iterator), but this function is not critical for performance
+    // (only used to generate a name when a user creates a new entity or rename one).
+    auto character = newName[i];
+    bool isAllowed =
+        allowUsageOfUnicodeIdentifierNames
+            ? GrammarTerminals::IsAllowedInIdentifier(character)
+            : legacyAllowedCharacters.find(character) != gd::String::npos;
+
     // Replace all unallowed letters by an underscore.
-    if (allowedCharacters.find_first_of(std::u32string(1, newName[i])) == gd::String::npos) {
+    if (!isAllowed) {
       newName.replace(i, 1, '_');
     }
   }
diff --git a/Core/GDCore/Project/Project.h b/Core/GDCore/Project/Project.h
index e3026c4c9a..7a964cc10e 100644
--- a/Core/GDCore/Project/Project.h
+++ b/Core/GDCore/Project/Project.h
@@ -975,10 +975,24 @@ class GD_CORE_API Project : public ObjectsContainer {
 
   ///@}
 
-  /** \name Other
+  /** \name Identifier names
    */
   ///@{
 
+  /**
+   * Check if unicode names are allowed in identifier names.
+   * \see IsNameSafe
+   * \see GetSafeName
+   */
+  static bool IsUsageOfUnicodeIdentifierNamesAllowed() { return allowUsageOfUnicodeIdentifierNames; };
+
+  /**
+   * Set if unicode names are allowed in identifier names.
+   * \see IsNameSafe
+   * \see GetSafeName
+   */
+  static void AllowUsageOfUnicodeIdentifierNames(bool enable);
+
   /**
    * Return true if \a name is valid (can be used safely for an object,
    * behavior, events function name, etc...).
@@ -989,7 +1003,7 @@ class GD_CORE_API Project : public ObjectsContainer {
    * Return a name, based on the one passed in parameter, that can be safely used
    * for an object, behavior, events function name, etc...
    */
-  static gd::String GetSafeName(const gd::String& name); 
+  static gd::String GetSafeName(const gd::String& name);
   ///@}
 
   /** \name External source files
@@ -1124,6 +1138,8 @@ class GD_CORE_API Project : public ObjectsContainer {
                                         ///< time the project was saved.
   mutable unsigned int gdBuildVersion;  ///< The GD build version used the last
                                         ///< time the project was saved.
+
+  static bool allowUsageOfUnicodeIdentifierNames;
 };
 
 }  // namespace gd
diff --git a/Core/tests/ExpressionParser2.cpp b/Core/tests/ExpressionParser2.cpp
index 41c9eb9bc8..de63bbaad3 100644
--- a/Core/tests/ExpressionParser2.cpp
+++ b/Core/tests/ExpressionParser2.cpp
@@ -26,7 +26,7 @@ TEST_CASE("ExpressionParser2", "[common][events]") {
 
   auto &myGroup = layout1.GetObjectGroups().InsertNew("MyGroup", 0);
   myGroup.AddObject(myObject.GetName());
-  
+
   layout1.InsertNewObject(project, "MyExtension::Sprite", "MySpriteObject", 1);
   layout1.InsertNewObject(project,
                           "MyExtension::FakeObjectWithUnsupportedCapability",
@@ -340,6 +340,20 @@ TEST_CASE("ExpressionParser2", "[common][events]") {
               "Cannot find an expression with this name: Idontexist\n"
               "Double check that you've not made any typo in the name.");
     }
+    {
+      auto node = parser.ParseExpression("🅸🅳🅾🅽🆃🅴🆇🅸🆂🆃😄(\"hello\"");
+      REQUIRE(node != nullptr);
+
+      gd::ExpressionValidator validator(platform, project, layout1, "string");
+      node->Visit(validator);
+      REQUIRE(validator.GetFatalErrors().size() == 2);
+      REQUIRE(validator.GetFatalErrors()[0]->GetMessage() ==
+              "The list of parameters is not terminated. Add a closing "
+              "parenthesis to end the parameters.");
+      REQUIRE(validator.GetFatalErrors()[1]->GetMessage() ==
+              "Cannot find an expression with this name: 🅸🅳🅾🅽🆃🅴🆇🅸🆂🆃😄\n"
+              "Double check that you've not made any typo in the name.");
+    }
     {
       auto node = parser.ParseExpression("=\"test\"");
       REQUIRE(node != nullptr);
@@ -694,6 +708,17 @@ TEST_CASE("ExpressionParser2", "[common][events]") {
               "You must enter a number.");
       REQUIRE(validator.GetFatalErrors()[0]->GetStartPosition() == 0);
     }
+    {
+      auto node = parser.ParseExpression("ab😊d");
+      REQUIRE(node != nullptr);
+
+      gd::ExpressionValidator validator(platform, project, layout1, "number");
+      node->Visit(validator);
+      REQUIRE(validator.GetFatalErrors().size() == 1);
+      REQUIRE(validator.GetFatalErrors()[0]->GetMessage() ==
+              "You must enter a number.");
+      REQUIRE(validator.GetFatalErrors()[0]->GetStartPosition() == 0);
+    }
     {
       auto node = parser.ParseExpression("abcd[0]");
       REQUIRE(node != nullptr);
@@ -917,6 +942,26 @@ TEST_CASE("ExpressionParser2", "[common][events]") {
       node->Visit(validator);
       REQUIRE(validator.GetFatalErrors().size() == 0);
     }
+    {
+      auto node = parser.ParseExpression("😅");
+      REQUIRE(node != nullptr);
+      auto &identifierNode = dynamic_cast<gd::IdentifierNode &>(*node);
+      REQUIRE(identifierNode.identifierName == "😅");
+
+      gd::ExpressionValidator validator(platform, project, layout1, "object");
+      node->Visit(validator);
+      REQUIRE(validator.GetFatalErrors().size() == 0);
+    }
+    {
+      auto node = parser.ParseExpression("中文");
+      REQUIRE(node != nullptr);
+      auto &identifierNode = dynamic_cast<gd::IdentifierNode &>(*node);
+      REQUIRE(identifierNode.identifierName == "中文");
+
+      gd::ExpressionValidator validator(platform, project, layout1, "object");
+      node->Visit(validator);
+      REQUIRE(validator.GetFatalErrors().size() == 0);
+    }
 
     {
       auto node = parser.ParseExpression("Hello World 1");
@@ -1092,6 +1137,46 @@ TEST_CASE("ExpressionParser2", "[common][events]") {
       REQUIRE(textNode.text == "2");
       REQUIRE(identifierNode.identifierName == "three");
     }
+    SECTION("identifier parameter (unicode)") {
+      auto node = parser.ParseExpression(
+          "WhateverObject.WhateverBehavior::WhateverFunction(1, \"2\", 😄)");
+      REQUIRE(node != nullptr);
+      auto &functionNode = dynamic_cast<gd::FunctionCallNode &>(*node);
+      REQUIRE(functionNode.functionName == "WhateverFunction");
+      REQUIRE(functionNode.objectName == "WhateverObject");
+      REQUIRE(functionNode.behaviorName == "WhateverBehavior");
+      REQUIRE(functionNode.parameters.size() == 3);
+      auto &numberNode =
+          dynamic_cast<gd::NumberNode &>(*functionNode.parameters[0]);
+      auto &textNode =
+          dynamic_cast<gd::TextNode &>(*functionNode.parameters[1]);
+      auto &identifierNode =
+          dynamic_cast<gd::IdentifierNode &>(*functionNode.parameters[2]);
+
+      REQUIRE(numberNode.number == "1");
+      REQUIRE(textNode.text == "2");
+      REQUIRE(identifierNode.identifierName == "😄");
+    }
+    SECTION("unicode for object, behavior and function") {
+      auto node = parser.ParseExpression(
+          "🧸.🗣️::🔔(1, \"2\", 😄)");
+      REQUIRE(node != nullptr);
+      auto &functionNode = dynamic_cast<gd::FunctionCallNode &>(*node);
+      REQUIRE(functionNode.functionName == "🔔");
+      REQUIRE(functionNode.objectName == "🧸");
+      REQUIRE(functionNode.behaviorName == "🗣️");
+      REQUIRE(functionNode.parameters.size() == 3);
+      auto &numberNode =
+          dynamic_cast<gd::NumberNode &>(*functionNode.parameters[0]);
+      auto &textNode =
+          dynamic_cast<gd::TextNode &>(*functionNode.parameters[1]);
+      auto &identifierNode =
+          dynamic_cast<gd::IdentifierNode &>(*functionNode.parameters[2]);
+
+      REQUIRE(numberNode.number == "1");
+      REQUIRE(textNode.text == "2");
+      REQUIRE(identifierNode.identifierName == "😄");
+    }
   }
 
   SECTION("Valid function calls ('number|string' type)") {
@@ -1669,7 +1754,7 @@ TEST_CASE("ExpressionParser2", "[common][events]") {
       auto &identifierNode = dynamic_cast<gd::IdentifierNode &>(*node);
       REQUIRE(identifierNode.identifierName == "myVariable");
       REQUIRE(identifierNode.childIdentifierName == "myChild");
-      
+
       gd::ExpressionValidator validator(platform, project, layout1, "scenevar");
       node->Visit(validator);
       REQUIRE(validator.GetFatalErrors().size() == 0);
@@ -1766,14 +1851,14 @@ TEST_CASE("ExpressionParser2", "[common][events]") {
       REQUIRE(identifierObject2Node.identifierName == "MyObject2");
       REQUIRE(variable1Node.identifierName == "MyVar1");
       REQUIRE(variable2Node.identifierName == "MyVar2");
-      
+
       auto variable1ObjectName = gd::ExpressionVariableOwnerFinder::GetObjectName(
           platform, project, layout1, "", variable1Node);
       REQUIRE(variable1ObjectName == "MyObject1");
       auto variable2ObjectName = gd::ExpressionVariableOwnerFinder::GetObjectName(
           platform, project, layout1, "", variable2Node);
       REQUIRE(variable2ObjectName == "MyObject2");
-      
+
       gd::ExpressionValidator validator(platform, project, layout1, "string");
       node->Visit(validator);
       REQUIRE(validator.GetFatalErrors().size() == 0);
@@ -1797,14 +1882,14 @@ TEST_CASE("ExpressionParser2", "[common][events]") {
       REQUIRE(identifierObject1Node.identifierName == "MyObject1");
       REQUIRE(variable1Node.identifierName == "MyVar1");
       REQUIRE(variable2Node.identifierName == "MyVar2");
-      
+
       auto variable1ObjectName = gd::ExpressionVariableOwnerFinder::GetObjectName(
           platform, project, layout1, "", variable1Node);
       REQUIRE(variable1ObjectName == "MyObject1");
       auto variable2ObjectName = gd::ExpressionVariableOwnerFinder::GetObjectName(
           platform, project, layout1, "", variable2Node);
       REQUIRE(variable2ObjectName == "MyObject1");
-      
+
       gd::ExpressionValidator validator(platform, project, layout1, "string");
       node->Visit(validator);
       REQUIRE(validator.GetFatalErrors().size() == 0);
@@ -1821,11 +1906,11 @@ TEST_CASE("ExpressionParser2", "[common][events]") {
           dynamic_cast<gd::IdentifierNode &>(*functionNode.parameters[0]);
 
       REQUIRE(variable1Node.identifierName == "MyVar1");
-      
+
       auto variable1ObjectName = gd::ExpressionVariableOwnerFinder::GetObjectName(
           platform, project, layout1, "MySpriteObject", variable1Node);
       REQUIRE(variable1ObjectName == "MySpriteObject");
-      
+
       gd::ExpressionValidator validator(platform, project, layout1, "number");
       node->Visit(validator);
       REQUIRE(validator.GetFatalErrors().size() == 0);
@@ -1843,11 +1928,11 @@ TEST_CASE("ExpressionParser2", "[common][events]") {
 
       REQUIRE(variable1Node.identifierName == "MyVar1");
       REQUIRE(variable1Node.childIdentifierName == "MyChild");
-      
+
       auto variable1ObjectName = gd::ExpressionVariableOwnerFinder::GetObjectName(
           platform, project, layout1, "MySpriteObject", variable1Node);
       REQUIRE(variable1ObjectName == "MySpriteObject");
-      
+
       gd::ExpressionValidator validator(platform, project, layout1, "number");
       node->Visit(validator);
       REQUIRE(validator.GetFatalErrors().size() == 0);
diff --git a/GDJS/GDJS/Events/CodeGeneration/MetadataDeclarationHelper.cpp b/GDJS/GDJS/Events/CodeGeneration/MetadataDeclarationHelper.cpp
index 2f34f1b8bc..dcffc5ddda 100644
--- a/GDJS/GDJS/Events/CodeGeneration/MetadataDeclarationHelper.cpp
+++ b/GDJS/GDJS/Events/CodeGeneration/MetadataDeclarationHelper.cpp
@@ -1352,7 +1352,7 @@ void MetadataDeclarationHelper::DeclareEventsFunctionParameters(
 }
 
 gd::String MetadataDeclarationHelper::GetExtensionCodeNamespacePrefix(
-    const gd::EventsFunctionsExtension eventsFunctionsExtension) {
+    const gd::EventsFunctionsExtension &eventsFunctionsExtension) {
   return "gdjs.evtsExt__" + EventsCodeNameMangler::GetMangledName(
                                 eventsFunctionsExtension.GetName());
 }
diff --git a/GDJS/GDJS/Events/CodeGeneration/MetadataDeclarationHelper.h b/GDJS/GDJS/Events/CodeGeneration/MetadataDeclarationHelper.h
index baeacd5143..f70e6323b3 100644
--- a/GDJS/GDJS/Events/CodeGeneration/MetadataDeclarationHelper.h
+++ b/GDJS/GDJS/Events/CodeGeneration/MetadataDeclarationHelper.h
@@ -66,10 +66,30 @@ public:
       const gd::EventsBasedObject &eventsBasedObject,
       std::map<gd::String, gd::String> &objectMethodMangledNames);
 
+  /** Generate the namespace prefix for an extension. */
+  static gd::String GetExtensionCodeNamespacePrefix(
+      const gd::EventsFunctionsExtension &eventsFunctionsExtension);
+
+  /** Generate the fully qualified name for a free function. */
   static gd::String GetFreeFunctionCodeName(
       const gd::EventsFunctionsExtension &eventsFunctionsExtension,
       const gd::EventsFunction &eventsFunction);
 
+  /** Generate the namespace for a free function. */
+  static gd::String
+  GetFreeFunctionCodeNamespace(const gd::EventsFunction &eventsFunction,
+                               const gd::String &codeNamespacePrefix);
+
+  /** Generate the namespace for a behavior function. */
+  static gd::String GetBehaviorFunctionCodeNamespace(
+      const gd::EventsBasedBehavior &eventsBasedBehavior,
+      const gd::String &codeNamespacePrefix);
+
+  /** Generate the namespace for an object function. */
+  static gd::String
+  GetObjectFunctionCodeNamespace(const gd::EventsBasedObject &eventsBasedObject,
+                                 const gd::String &codeNamespacePrefix);
+
   /**
    * Declare an extension from an events based extension.
    */
@@ -292,24 +312,6 @@ private:
       gd::MultipleInstructionMetadata &multipleInstructionMetadata,
       const int userDefinedFirstParameterIndex);
 
-  static gd::String GetExtensionCodeNamespacePrefix(
-      const gd::EventsFunctionsExtension eventsFunctionsExtension);
-
-  /** Generate the namespace for a free function. */
-  static gd::String
-  GetFreeFunctionCodeNamespace(const gd::EventsFunction &eventsFunction,
-                               const gd::String &codeNamespacePrefix);
-
-  /** Generate the namespace for a behavior function. */
-  static gd::String GetBehaviorFunctionCodeNamespace(
-      const gd::EventsBasedBehavior &eventsBasedBehavior,
-      const gd::String &codeNamespacePrefix);
-
-  /** Generate the namespace for an object function. */
-  static gd::String
-  GetObjectFunctionCodeNamespace(const gd::EventsBasedObject &eventsBasedObject,
-                                 const gd::String &codeNamespacePrefix);
-
   static gd::String RemoveTrailingDot(const gd::String &description);
 
   static gd::String
diff --git a/GDevelop.js/Bindings/Bindings.idl b/GDevelop.js/Bindings/Bindings.idl
index d799cff337..554468d924 100644
--- a/GDevelop.js/Bindings/Bindings.idl
+++ b/GDevelop.js/Bindings/Bindings.idl
@@ -521,6 +521,8 @@ interface Project {
     void SerializeTo([Ref] SerializerElement element);
     void UnserializeFrom([Const, Ref] SerializerElement element);
 
+    boolean STATIC_IsUsageOfUnicodeIdentifierNamesAllowed();
+    void STATIC_AllowUsageOfUnicodeIdentifierNames(boolean enable);
     boolean STATIC_IsNameSafe([Const] DOMString name);
     [Const, Value] DOMString STATIC_GetSafeName([Const] DOMString name);
 
@@ -1291,7 +1293,7 @@ interface AbstractFunctionMetadata {
     [Ref] AbstractFunctionMetadata SetDefaultValue([Const] DOMString defaultValue);
     [Ref] AbstractFunctionMetadata SetParameterLongDescription([Const] DOMString longDescription);
     [Ref] AbstractFunctionMetadata SetParameterExtraInfo([Const] DOMString extraInfo);
-    
+
     [Ref] AbstractFunctionMetadata SetHidden();
     [Ref] AbstractFunctionMetadata SetPrivate();
 
@@ -1354,7 +1356,7 @@ interface InstructionMetadata {
     [Ref] InstructionMetadata MarkAsComplex();
 
     [Ref] InstructionMetadata GetCodeExtraInformation();
-    
+
     [Ref] InstructionMetadata SetFunctionName([Const] DOMString functionName_);
     [Ref] InstructionMetadata SetAsyncFunctionName([Const] DOMString functionName_);
     [Const, Ref] DOMString GetFunctionName();
@@ -1415,7 +1417,7 @@ interface ExpressionMetadata {
     [Const, Ref] DOMString GetRequiredBaseObjectCapability();
 
     [Ref] ExpressionMetadata GetCodeExtraInformation();
-    
+
     [Ref] ExpressionMetadata SetFunctionName([Const] DOMString functionName);
     [Const, Ref] DOMString GetFunctionName();
     [Ref] ExpressionMetadata SetStatic();
@@ -3397,7 +3399,7 @@ interface JsCodeEvent {
 [Prefix="gdjs::"]
 interface MetadataDeclarationHelper {
     void MetadataDeclarationHelper();
-    
+
     void STATIC_DeclareExtension(
         [Ref] PlatformExtension extension,
         [Const, Ref] EventsFunctionsExtension eventsFunctionsExtension);
@@ -3422,10 +3424,25 @@ interface MetadataDeclarationHelper {
         [Const, Ref] EventsBasedObject eventsBasedObject,
         [Ref] MapStringString objectMethodMangledNames);
 
+    [Const, Value] DOMString STATIC_GetExtensionCodeNamespacePrefix(
+        [Const, Ref] EventsFunctionsExtension eventsFunctionsExtension);
+
     [Const, Value] DOMString STATIC_GetFreeFunctionCodeName(
         [Const, Ref] EventsFunctionsExtension eventsFunctionsExtension,
         [Const, Ref] EventsFunction eventsFunction);
 
+    [Const, Value] DOMString STATIC_GetFreeFunctionCodeNamespace(
+        [Const, Ref] EventsFunction eventsFunction,
+        [Const] DOMString codeNamespacePrefix);
+
+    [Const, Value] DOMString STATIC_GetBehaviorFunctionCodeNamespace(
+        [Const, Ref] EventsBasedBehavior eventsBasedBehavior,
+        [Const] DOMString codeNamespacePrefix);
+
+    [Const, Value] DOMString STATIC_GetObjectFunctionCodeNamespace(
+        [Const, Ref] EventsBasedObject eventsBasedObject,
+        [Const] DOMString codeNamespacePrefix);
+
     boolean STATIC_IsBehaviorLifecycleEventsFunction([Const] DOMString functionName);
     boolean STATIC_IsObjectLifecycleEventsFunction([Const] DOMString functionName);
     boolean STATIC_IsExtensionLifecycleEventsFunction([Const] DOMString functionName);
diff --git a/GDevelop.js/Bindings/Wrapper.cpp b/GDevelop.js/Bindings/Wrapper.cpp
index 8b92b49841..24b2b15689 100644
--- a/GDevelop.js/Bindings/Wrapper.cpp
+++ b/GDevelop.js/Bindings/Wrapper.cpp
@@ -522,6 +522,8 @@ typedef ExtensionAndMetadata<ExpressionMetadata> ExtensionAndExpressionMetadata;
 
 #define STATIC_CreateNewGDJSProject CreateNewGDJSProject
 #define STATIC_InitializePlatforms InitializePlatforms
+#define STATIC_IsUsageOfUnicodeIdentifierNamesAllowed IsUsageOfUnicodeIdentifierNamesAllowed
+#define STATIC_AllowUsageOfUnicodeIdentifierNames AllowUsageOfUnicodeIdentifierNames
 #define STATIC_IsNameSafe IsNameSafe
 #define STATIC_GetSafeName GetSafeName
 #define STATIC_ToJSON ToJSON
@@ -698,7 +700,11 @@ typedef ExtensionAndMetadata<ExpressionMetadata> ExtensionAndExpressionMetadata;
 #define STATIC_DeclareExtension DeclareExtension
 #define STATIC_GenerateBehaviorMetadata GenerateBehaviorMetadata
 #define STATIC_GenerateObjectMetadata GenerateObjectMetadata
+#define STATIC_GetExtensionCodeNamespacePrefix GetExtensionCodeNamespacePrefix
 #define STATIC_GetFreeFunctionCodeName GetFreeFunctionCodeName
+#define STATIC_GetFreeFunctionCodeNamespace GetFreeFunctionCodeNamespace
+#define STATIC_GetBehaviorFunctionCodeNamespace GetBehaviorFunctionCodeNamespace
+#define STATIC_GetObjectFunctionCodeNamespace GetObjectFunctionCodeNamespace
 #define STATIC_IsBehaviorLifecycleEventsFunction IsBehaviorLifecycleEventsFunction
 #define STATIC_IsObjectLifecycleEventsFunction IsObjectLifecycleEventsFunction
 #define STATIC_IsExtensionLifecycleEventsFunction IsExtensionLifecycleEventsFunction
diff --git a/GDevelop.js/__tests__/Core.js b/GDevelop.js/__tests__/Core.js
index 006746e87c..7c8ee696ec 100644
--- a/GDevelop.js/__tests__/Core.js
+++ b/GDevelop.js/__tests__/Core.js
@@ -99,7 +99,8 @@ describe('libGD.js', function () {
       expect(project.hasExternalLayoutNamed('My layout')).toBe(false);
     });
 
-    it('should validate object names', function () {
+    it('should validate object names (legacy)', function () {
+      gd.Project.allowUsageOfUnicodeIdentifierNames(false);
       expect(gd.Project.isNameSafe('ThisNameIs_Ok_123')).toBe(true);
       expect(gd.Project.isNameSafe('ThisName IsNot_Ok_123')).toBe(false);
       expect(gd.Project.isNameSafe('ThisNameIsNot_Ok!')).toBe(false);
@@ -113,6 +114,25 @@ describe('libGD.js', function () {
       expect(gd.Project.getSafeName('9')).toBe('_9');
     });
 
+    it('should validate object names (unicode)', function () {
+      gd.Project.allowUsageOfUnicodeIdentifierNames(true);
+      expect(gd.Project.isNameSafe('ThisNameIs_Ok_123')).toBe(true);
+      expect(gd.Project.isNameSafe('ThisNameIs_👍_123')).toBe(true);
+      expect(gd.Project.isNameSafe('ThisName IsNot_Ok_123')).toBe(false);
+      expect(gd.Project.isNameSafe('ThisName()IsNot_Ok_123')).toBe(false);
+      expect(gd.Project.isNameSafe('ThisNameIsNot_Ok!')).toBe(false);
+      expect(gd.Project.isNameSafe('1ThisNameIsNot_Ok_123')).toBe(false);
+      expect(gd.Project.getSafeName('ThisNameIs_Ok_123')).toBe('ThisNameIs_Ok_123');
+      expect(gd.Project.getSafeName('ThisNameIs_👍_123')).toBe('ThisNameIs_👍_123');
+      expect(gd.Project.getSafeName('ThisName IsNot_Ok_123')).toBe('ThisName_IsNot_Ok_123');
+      expect(gd.Project.getSafeName('ThisName()IsNot_Ok_123')).toBe('ThisName__IsNot_Ok_123');
+      expect(gd.Project.getSafeName('ThisNameIsNot_Ok!')).toBe('ThisNameIsNot_Ok_');
+      expect(gd.Project.getSafeName('1ThisNameIsNot_Ok_123')).toBe('_1ThisNameIsNot_Ok_123');
+      expect(gd.Project.getSafeName('官话 name')).toBe('官话_name');
+      expect(gd.Project.getSafeName('')).toBe('Unnamed');
+      expect(gd.Project.getSafeName('9')).toBe('_9');
+    });
+
     it('should have a list of extensions', function () {
       expect(
         gd.UsedExtensionsFinder.scanProject(project)
diff --git a/GDevelop.js/__tests__/MetadataDeclarationHelper.js b/GDevelop.js/__tests__/MetadataDeclarationHelper.js
index 98ddf4758d..383e0aeaed 100644
--- a/GDevelop.js/__tests__/MetadataDeclarationHelper.js
+++ b/GDevelop.js/__tests__/MetadataDeclarationHelper.js
@@ -45,16 +45,16 @@ describe('MetadataDeclarationHelper', () => {
     project.delete();
   });
 
-  it('can create metadata for free actions with an underscore', () => {
+  it('can create metadata for free actions with an underscore and unicode characters', () => {
     const extension = new gd.PlatformExtension();
     const project = new gd.Project();
 
     const eventExtension = project.insertNewEventsFunctionsExtension(
-      'MyExtension',
+      'My🧩Extension',
       0
     );
     const eventFunction = eventExtension.insertNewEventsFunction(
-      'My_Function',
+      'My_📝Function',
       0
     );
     eventFunction.setFunctionType(gd.EventsFunction.Action);
@@ -68,10 +68,10 @@ describe('MetadataDeclarationHelper', () => {
     );
     metadataDeclarationHelper.delete();
 
-    expect(extension.getAllActions().has('My_Function')).toBe(true);
-    const action = extension.getAllActions().get('My_Function');
+    expect(extension.getAllActions().has('My_📝Function')).toBe(true);
+    const action = extension.getAllActions().get('My_📝Function');
     expect(action.getFunctionName()).toBe(
-      'gdjs.evtsExt__MyExtension__My_Function.func'
+      'gdjs.evtsExt__My_129513Extension__My__128221Function.func'
     );
 
     extension.delete();
diff --git a/GDevelop.js/types/gdmetadatadeclarationhelper.js b/GDevelop.js/types/gdmetadatadeclarationhelper.js
index c1fc0ce966..7c7263c3bf 100644
--- a/GDevelop.js/types/gdmetadatadeclarationhelper.js
+++ b/GDevelop.js/types/gdmetadatadeclarationhelper.js
@@ -5,7 +5,11 @@ declare class gdMetadataDeclarationHelper {
   generateFreeFunctionMetadata(project: gdProject, extension: gdPlatformExtension, eventsFunctionsExtension: gdEventsFunctionsExtension, eventsFunction: gdEventsFunction): gdAbstractFunctionMetadata;
   static generateBehaviorMetadata(project: gdProject, extension: gdPlatformExtension, eventsFunctionsExtension: gdEventsFunctionsExtension, eventsBasedBehavior: gdEventsBasedBehavior, behaviorMethodMangledNames: gdMapStringString): gdBehaviorMetadata;
   static generateObjectMetadata(project: gdProject, extension: gdPlatformExtension, eventsFunctionsExtension: gdEventsFunctionsExtension, eventsBasedObject: gdEventsBasedObject, objectMethodMangledNames: gdMapStringString): gdObjectMetadata;
+  static getExtensionCodeNamespacePrefix(eventsFunctionsExtension: gdEventsFunctionsExtension): string;
   static getFreeFunctionCodeName(eventsFunctionsExtension: gdEventsFunctionsExtension, eventsFunction: gdEventsFunction): string;
+  static getFreeFunctionCodeNamespace(eventsFunction: gdEventsFunction, codeNamespacePrefix: string): string;
+  static getBehaviorFunctionCodeNamespace(eventsBasedBehavior: gdEventsBasedBehavior, codeNamespacePrefix: string): string;
+  static getObjectFunctionCodeNamespace(eventsBasedObject: gdEventsBasedObject, codeNamespacePrefix: string): string;
   static isBehaviorLifecycleEventsFunction(functionName: string): boolean;
   static isObjectLifecycleEventsFunction(functionName: string): boolean;
   static isExtensionLifecycleEventsFunction(functionName: string): boolean;
diff --git a/GDevelop.js/types/gdproject.js b/GDevelop.js/types/gdproject.js
index 1657ee5308..7e470d27e3 100644
--- a/GDevelop.js/types/gdproject.js
+++ b/GDevelop.js/types/gdproject.js
@@ -104,6 +104,8 @@ declare class gdProject extends gdObjectsContainer {
   exposeResources(worker: gdArbitraryResourceWorker): void;
   serializeTo(element: gdSerializerElement): void;
   unserializeFrom(element: gdSerializerElement): void;
+  static isUsageOfUnicodeIdentifierNamesAllowed(): boolean;
+  static allowUsageOfUnicodeIdentifierNames(enable: boolean): void;
   static isNameSafe(name: string): boolean;
   static getSafeName(name: string): string;
   getTypeOfBehavior(layout: gdLayout, name: string, searchInGroups: boolean): string;
diff --git a/newIDE/app/src/EventsFunctionsExtensionsLoader/index.js b/newIDE/app/src/EventsFunctionsExtensionsLoader/index.js
index 304ebbfafd..29325c167f 100644
--- a/newIDE/app/src/EventsFunctionsExtensionsLoader/index.js
+++ b/newIDE/app/src/EventsFunctionsExtensionsLoader/index.js
@@ -1,7 +1,6 @@
 // @flow
 import { type I18n as I18nType } from '@lingui/core';
 import { mapVector, mapFor } from '../Utils/MapFor';
-import { caseSensitiveSlug } from '../Utils/CaseSensitiveSlug';
 
 const gd: libGDevelop = global.gd;
 
@@ -32,56 +31,10 @@ type OptionsForGeneration = {
 };
 
 type CodeGenerationContext = {|
-  codeNamespacePrefix: string,
+  codeNamespacePrefix: string, // TODO: could this reworked to avoid this entirely?
   extensionIncludeFiles: Array<string>,
 |};
 
-const mangleName = (name: string) => {
-  return caseSensitiveSlug(name, '_', []);
-};
-
-const getExtensionCodeNamespacePrefix = (
-  eventsFunctionsExtension: gdEventsFunctionsExtension
-) => {
-  return 'gdjs.evtsExt__' + mangleName(eventsFunctionsExtension.getName());
-};
-
-/** Generate the namespace for a free function. */
-const getFreeFunctionCodeNamespace = (
-  eventsFunction: gdEventsFunction,
-  codeNamespacePrefix: string
-) => {
-  return codeNamespacePrefix + '__' + mangleName(eventsFunction.getName());
-};
-
-export const getFreeFunctionCodeName = (
-  eventsFunctionsExtension: gdEventsFunctionsExtension,
-  eventsFunction: gdEventsFunction
-) => {
-  return (
-    getFreeFunctionCodeNamespace(
-      eventsFunction,
-      getExtensionCodeNamespacePrefix(eventsFunctionsExtension)
-    ) + '.func'
-  );
-};
-
-/** Generate the namespace for a behavior function. */
-const getBehaviorFunctionCodeNamespace = (
-  eventsBasedBehavior: gdEventsBasedBehavior,
-  codeNamespacePrefix: string
-) => {
-  return codeNamespacePrefix + '__' + mangleName(eventsBasedBehavior.getName());
-};
-
-/** Generate the namespace for an object function. */
-const getObjectFunctionCodeNamespace = (
-  eventsBasedObject: gdEventsBasedObject,
-  codeNamespacePrefix: string
-) => {
-  return codeNamespacePrefix + '__' + mangleName(eventsBasedObject.getName());
-};
-
 /**
  * Load all events functions of a project in extensions
  */
@@ -160,18 +113,15 @@ const loadProjectEventsFunctionsExtension = (
 const getExtensionIncludeFiles = (
   project: gdProject,
   eventsFunctionsExtension: gdEventsFunctionsExtension,
-  options: Options,
-  codeNamespacePrefix: string
+  options: Options
 ): Array<string> => {
   return mapFor(0, eventsFunctionsExtension.getEventsFunctionsCount(), i => {
     const eventsFunction = eventsFunctionsExtension.getEventsFunctionAt(i);
 
-    const codeNamespace = getFreeFunctionCodeNamespace(
-      eventsFunction,
-      codeNamespacePrefix
+    const functionName = gd.MetadataDeclarationHelper.getFreeFunctionCodeName(
+      eventsFunctionsExtension,
+      eventsFunction
     );
-    // TODO Use getFreeFunctionCodeName.
-    const functionName = codeNamespace + '.func';
 
     return options.eventsFunctionCodeWriter.getIncludeFileFor(functionName);
   }).filter(Boolean);
@@ -191,14 +141,14 @@ const generateEventsFunctionExtension = (
     eventsFunctionsExtension
   );
 
-  const codeNamespacePrefix =
-    'gdjs.evtsExt__' + mangleName(eventsFunctionsExtension.getName());
+  const codeNamespacePrefix = gd.MetadataDeclarationHelper.getExtensionCodeNamespacePrefix(
+    eventsFunctionsExtension
+  );
 
   const extensionIncludeFiles = getExtensionIncludeFiles(
     project,
     eventsFunctionsExtension,
-    options,
-    codeNamespacePrefix
+    options
   );
   const codeGenerationContext = {
     codeNamespacePrefix,
@@ -276,14 +226,14 @@ const generateEventsFunctionExtensionMetadata = (
     eventsFunctionsExtension
   );
 
-  const codeNamespacePrefix =
-    'gdjs.evtsExt__' + mangleName(eventsFunctionsExtension.getName());
+  const codeNamespacePrefix = gd.MetadataDeclarationHelper.getExtensionCodeNamespacePrefix(
+    eventsFunctionsExtension
+  );
 
   const extensionIncludeFiles = getExtensionIncludeFiles(
     project,
     eventsFunctionsExtension,
-    options,
-    codeNamespacePrefix
+    options
   );
   const codeGenerationContext = {
     codeNamespacePrefix,
@@ -369,7 +319,7 @@ const generateFreeFunction = (
     const eventsFunctionsExtensionCodeGenerator = new gd.EventsFunctionsExtensionCodeGenerator(
       project
     );
-    const codeNamespace = getFreeFunctionCodeNamespace(
+    const codeNamespace = gd.MetadataDeclarationHelper.getFreeFunctionCodeNamespace(
       eventsFunction,
       codeGenerationContext.codeNamespacePrefix
     );
@@ -398,8 +348,10 @@ const generateFreeFunction = (
     eventsFunctionsExtensionCodeGenerator.delete();
     metadataDeclarationHelper.delete();
 
-    // TODO Implement an helper function for free function names.
-    const functionName = codeNamespace + '.func';
+    const functionName = gd.MetadataDeclarationHelper.getFreeFunctionCodeName(
+      eventsFunctionsExtension,
+      eventsFunction
+    );
     return options.eventsFunctionCodeWriter
       .writeFunctionCode(functionName, code)
       .then(() => {});
@@ -476,7 +428,7 @@ function generateBehavior(
 
     // Generate code for the behavior and its methods
     if (!options.skipCodeGeneration) {
-      const codeNamespace = getBehaviorFunctionCodeNamespace(
+      const codeNamespace = gd.MetadataDeclarationHelper.getBehaviorFunctionCodeNamespace(
         eventsBasedBehavior,
         codeGenerationContext.codeNamespacePrefix
       );
@@ -538,7 +490,7 @@ function generateBehaviorMetadata(
     behaviorMethodMangledNames
   );
 
-  const codeNamespace = getBehaviorFunctionCodeNamespace(
+  const codeNamespace = gd.MetadataDeclarationHelper.getBehaviorFunctionCodeNamespace(
     eventsBasedBehavior,
     codeGenerationContext.codeNamespacePrefix
   );
@@ -578,7 +530,7 @@ function generateObject(
 
     // Generate code for the object and its methods
     if (!options.skipCodeGeneration) {
-      const codeNamespace = getObjectFunctionCodeNamespace(
+      const codeNamespace = gd.MetadataDeclarationHelper.getObjectFunctionCodeNamespace(
         eventsBasedObject,
         codeGenerationContext.codeNamespacePrefix
       );
@@ -640,7 +592,7 @@ function generateObjectMetadata(
     objectMethodMangledNames
   );
 
-  const codeNamespace = getObjectFunctionCodeNamespace(
+  const codeNamespace = gd.MetadataDeclarationHelper.getObjectFunctionCodeNamespace(
     eventsBasedObject,
     codeGenerationContext.codeNamespacePrefix
   );
diff --git a/newIDE/app/src/MainFrame/Preferences/PreferencesContext.js b/newIDE/app/src/MainFrame/Preferences/PreferencesContext.js
index 43ee1fd8ae..55c320d058 100644
--- a/newIDE/app/src/MainFrame/Preferences/PreferencesContext.js
+++ b/newIDE/app/src/MainFrame/Preferences/PreferencesContext.js
@@ -212,6 +212,7 @@ export type PreferencesValues = {|
   newProjectsDefaultFolder: string,
   newProjectsDefaultStorageProviderName: string,
   useShortcutToClosePreviewWindow: boolean,
+  allowUsageOfUnicodeIdentifierNames: boolean,
 |};
 
 /**
@@ -289,6 +290,7 @@ export type Preferences = {|
   |}) => ?InAppTutorialUserProgress,
   setNewProjectsDefaultFolder: (newProjectsDefaultFolder: string) => void,
   setUseShortcutToClosePreviewWindow: (enabled: boolean) => void,
+  setAllowUsageOfUnicodeIdentifierNames: (enabled: boolean) => void,
 |};
 
 export const initialPreferences = {
@@ -333,6 +335,7 @@ export const initialPreferences = {
     newProjectsDefaultFolder: app ? findDefaultFolder(app) : '',
     newProjectsDefaultStorageProviderName: 'Cloud',
     useShortcutToClosePreviewWindow: true,
+    allowUsageOfUnicodeIdentifierNames: false,
   },
   setLanguage: () => {},
   setThemeName: () => {},
@@ -389,6 +392,7 @@ export const initialPreferences = {
   setNewProjectsDefaultFolder: () => {},
   setNewProjectsDefaultStorageProviderName: () => {},
   setUseShortcutToClosePreviewWindow: () => {},
+  setAllowUsageOfUnicodeIdentifierNames: () => {},
 };
 
 const PreferencesContext = React.createContext<Preferences>(initialPreferences);
diff --git a/newIDE/app/src/MainFrame/Preferences/PreferencesDialog.js b/newIDE/app/src/MainFrame/Preferences/PreferencesDialog.js
index 1f6ffba133..bc50f1299c 100644
--- a/newIDE/app/src/MainFrame/Preferences/PreferencesDialog.js
+++ b/newIDE/app/src/MainFrame/Preferences/PreferencesDialog.js
@@ -69,6 +69,7 @@ const PreferencesDialog = ({ i18n, onClose }: Props) => {
     setUse3DEditor,
     setNewProjectsDefaultFolder,
     setUseShortcutToClosePreviewWindow,
+    setAllowUsageOfUnicodeIdentifierNames,
   } = React.useContext(PreferencesContext);
 
   const initialUse3DEditor = React.useRef<boolean>(values.use3DEditor);
@@ -354,6 +355,19 @@ const PreferencesDialog = ({ i18n, onClose }: Props) => {
               </Trans>
             }
           />
+          <Toggle
+            onToggle={(e, check) =>
+              setAllowUsageOfUnicodeIdentifierNames(check)
+            }
+            toggled={values.allowUsageOfUnicodeIdentifierNames}
+            labelPosition="right"
+            label={
+              <Trans>
+                Allow unicode characters (non English languages and emojis) in
+                object, behavior and other names (experimental)
+              </Trans>
+            }
+          />
           <Toggle
             onToggle={(e, check) => setUse3DEditor(check)}
             toggled={values.use3DEditor}
diff --git a/newIDE/app/src/MainFrame/Preferences/PreferencesProvider.js b/newIDE/app/src/MainFrame/Preferences/PreferencesProvider.js
index 140ab5b04c..b82b295d02 100644
--- a/newIDE/app/src/MainFrame/Preferences/PreferencesProvider.js
+++ b/newIDE/app/src/MainFrame/Preferences/PreferencesProvider.js
@@ -61,6 +61,12 @@ export const loadPreferencesFromLocalStorage = (): ?PreferencesValues => {
       values.themeName = 'Blue Dark';
     }
 
+    // Synchronize the global state(s).
+    const gd: libGDevelop = global.gd;
+    gd.Project.allowUsageOfUnicodeIdentifierNames(
+      values.allowUsageOfUnicodeIdentifierNames
+    );
+
     return values;
   } catch (e) {
     return null;
@@ -159,6 +165,9 @@ export default class PreferencesProvider extends React.Component<Props, State> {
     setUseShortcutToClosePreviewWindow: this._setUseShortcutToClosePreviewWindow.bind(
       this
     ),
+    setAllowUsageOfUnicodeIdentifierNames: this._setAllowUsageOfUnicodeIdentifierNames.bind(
+      this
+    ),
   };
 
   componentDidMount() {
@@ -819,6 +828,21 @@ export default class PreferencesProvider extends React.Component<Props, State> {
     );
   }
 
+  _setAllowUsageOfUnicodeIdentifierNames(enable: boolean) {
+    const gd: libGDevelop = global.gd;
+    gd.Project.allowUsageOfUnicodeIdentifierNames(enable);
+
+    this.setState(
+      state => ({
+        values: {
+          ...state.values,
+          allowUsageOfUnicodeIdentifierNames: enable,
+        },
+      }),
+      () => this._persistValuesToLocalStorage(this.state)
+    );
+  }
+
   render() {
     return (
       <PreferencesContext.Provider value={this.state}>
diff --git a/newIDE/app/src/Utils/CaseSensitiveSlug.js b/newIDE/app/src/Utils/CaseSensitiveSlug.js
deleted file mode 100644
index 3f5c6cb287..0000000000
--- a/newIDE/app/src/Utils/CaseSensitiveSlug.js
+++ /dev/null
@@ -1,34 +0,0 @@
-// @flow
-
-/*
- * Case Sensitive Slug method
- * Inspired by Aaron Stannard module (https://github.com/Aaronontheweb/node-slugs)
- */
-export const caseSensitiveSlug = (
-  incString: string,
-  separator?: string,
-  preserved?: Array<string>
-): string => {
-  var p = ['.', '=', '-'];
-  var s = '-';
-
-  if (typeof preserved != 'undefined') {
-    p = preserved;
-  }
-
-  if (typeof separator != 'undefined') {
-    s = separator;
-  }
-
-  return incString
-    .replace(/ü/g, 'ue')
-    .replace(/ä/g, 'ae')
-    .replace(/ö/g, 'oe')
-    .replace(/ß/g, 'ss')
-    .replace(new RegExp('[' + p.join('') + ']', 'g'), ' ') //  replace preserved characters with spaces
-    .replace(/-{2,}/g, ' ') //  remove duplicate spaces
-    .replace(/^\s\s*/, '')
-    .replace(/\s\s*$/, '') //  trim both sides of string
-    .replace(/[^\w ]/gi, '') //  replaces all non-alphanumeric with empty string
-    .replace(/[ ]/gi, s); //  Convert spaces to dashes
-};