diff --git a/packages/strapi-plugin-content-type-builder/services/ContentTypes.js b/packages/strapi-plugin-content-type-builder/services/ContentTypes.js
index f231cbde9b..e0399e0969 100644
--- a/packages/strapi-plugin-content-type-builder/services/ContentTypes.js
+++ b/packages/strapi-plugin-content-type-builder/services/ContentTypes.js
@@ -174,7 +174,7 @@ const editContentType = async (uid, { contentType, components = [] }) => {
     try {
       await apiHandler.clear(uid);
 
-      // generate new api squeleton
+      // generate new api skeleton
       await generateAPI({
         name: updatedContentType.schema.info.name,
         kind: updatedContentType.schema.kind,
diff --git a/packages/strapi-plugin-content-type-builder/services/schema-builder/index.js b/packages/strapi-plugin-content-type-builder/services/schema-builder/index.js
index 8dc84312fe..868443979a 100644
--- a/packages/strapi-plugin-content-type-builder/services/schema-builder/index.js
+++ b/packages/strapi-plugin-content-type-builder/services/schema-builder/index.js
@@ -93,7 +93,7 @@ function createSchemaBuilder({ components, contentTypes }) {
               via,
               allowedTypes: attribute.allowedTypes,
               plugin: 'upload',
-              required: attribute.required ? true : false,
+              required: !!attribute.required,
               configurable: configurable === false ? false : undefined,
             };
           } else {
diff --git a/packages/strapi-plugin-content-type-builder/services/schema-builder/schema-handler.js b/packages/strapi-plugin-content-type-builder/services/schema-builder/schema-handler.js
index 1a12cc9a71..c669a6f25a 100644
--- a/packages/strapi-plugin-content-type-builder/services/schema-builder/schema-handler.js
+++ b/packages/strapi-plugin-content-type-builder/services/schema-builder/schema-handler.js
@@ -51,6 +51,10 @@ module.exports = function createSchemaHandler(infos) {
       return state.uid;
     },
 
+    get writable() {
+      return _.get(state, 'plugin') !== 'admin';
+    },
+
     setUID(val) {
       modified = true;
 
@@ -201,6 +205,10 @@ module.exports = function createSchemaHandler(infos) {
 
     // save the schema to disk
     async flush() {
+      if (!this.writable) {
+        return;
+      }
+
       const initialPath = path.join(initialState.dir, initialState.filename);
       const filePath = path.join(state.dir, state.filename);
 
@@ -244,6 +252,10 @@ module.exports = function createSchemaHandler(infos) {
 
     // reset the schema to its initial value
     async rollback() {
+      if (!this.writable) {
+        return;
+      }
+
       const initialPath = path.join(initialState.dir, initialState.filename);
       const filePath = path.join(state.dir, state.filename);