diff --git a/back/src/Services/VariablesManager.ts b/back/src/Services/VariablesManager.ts
index c6b6f5fe..e8aaef25 100644
--- a/back/src/Services/VariablesManager.ts
+++ b/back/src/Services/VariablesManager.ts
@@ -51,6 +51,17 @@ export class VariablesManager {
         }
         const variables = await variablesRepository.loadVariables(this.roomUrl);
         for (const key in variables) {
+            // Let's only set variables if they are in the map (if the map has changed, maybe stored variables do not exist anymore)
+            if (this.variableObjects) {
+                const variableObject = this.variableObjects.get(key);
+                if (variableObject === undefined) {
+                    continue;
+                }
+                if (!variableObject.persist) {
+                    continue;
+                }
+            }
+
             this._variables.set(key, variables[key]);
         }
         return this;
@@ -146,8 +157,9 @@ export class VariablesManager {
      */
     setVariable(name: string, value: string, user: User): string | undefined | false {
         let readableBy: string | undefined;
+        let variableObject: Variable | undefined;
         if (this.variableObjects) {
-            const variableObject = this.variableObjects.get(name);
+            variableObject = this.variableObjects.get(name);
             if (variableObject === undefined) {
                 throw new Error('Trying to set a variable "' + name + '" that is not defined as an object in the map.');
             }
@@ -175,9 +187,13 @@ export class VariablesManager {
         }
 
         this._variables.set(name, value);
-        variablesRepository
-            .saveVariable(this.roomUrl, name, value)
-            .catch((e) => console.error("Error while saving variable in Redis:", e));
+
+        if (variableObject !== undefined && variableObject.persist) {
+            variablesRepository
+                .saveVariable(this.roomUrl, name, value)
+                .catch((e) => console.error("Error while saving variable in Redis:", e));
+        }
+
         return readableBy;
     }
 
diff --git a/docs/maps/scripting.md b/docs/maps/scripting.md
index 5f645b81..5be57ee1 100644
--- a/docs/maps/scripting.md
+++ b/docs/maps/scripting.md
@@ -55,10 +55,10 @@ Start by testing this with a simple message sent to the chat.
 
 **script.js**
 ```javascript
-WA.sendChatMessage('Hello world', 'Mr Robot');
+WA.chat.sendChatMessage('Hello world', 'Mr Robot');
 ```
 
-The `WA` objects contains a number of useful methods enabling you to interact with the WorkAdventure game. For instance, `WA.sendChatMessage` opens the chat and adds a message in it.
+The `WA` objects contains a number of useful methods enabling you to interact with the WorkAdventure game. For instance, `WA.chat.sendChatMessage` opens the chat and adds a message in it.
 
 In your browser console, when you open the map, the chat message should be displayed right away.