diff --git a/book/book.toml b/book/book.toml
index c324f71a..24aa38b8 100644
--- a/book/book.toml
+++ b/book/book.toml
@@ -1,10 +1,9 @@
 [book]
 language = "en"
-multilingual = false
 src = "src"
 title = "Lens Book"
 
 [output.html]
 git-repository-url = "https://github.com/samply/lens/tree/develop/book"
-git-repository-icon = "fa-github"
+git-repository-icon = "fab-github"
 edit-url-template = "https://github.com/samply/lens/edit/develop/book/{path}"
diff --git a/src/stores/catalogue.ts b/src/stores/catalogue.ts
index d691c891..75ebfef1 100644
--- a/src/stores/catalogue.ts
+++ b/src/stores/catalogue.ts
@@ -322,20 +322,22 @@ export const getCriteriaFromKey = (
 };
 
 /**
- * Set the catalogue. A warning is logged to the browser console if the catalogue does not match the JSON schema.
+ * Set the catalogue. A warning is logged to the browser console if the catalogue does not match the JSON schema. Note that the function makes a deep copy of the catalogue so modifying the original object has no effect.
  */
-export function setCatalogue(cat: Catalogue) {
-    catalogue.set(cat);
+export function setCatalogue(newCatalogue: Catalogue) {
+    // Make a copy to avoid modifying the original object
+    const catalogueCopy = structuredClone(newCatalogue);
     const ajv = new Ajv({
         allErrors: true,
         removeAdditional: true,
     });
     addFormats(ajv);
-    const valid = ajv.validate(catalogueSchema, cat);
+    const valid = ajv.validate(catalogueSchema, catalogueCopy);
     if (!valid) {
         console.warn(
             "Catalogue does not conform with JSON schema: " +
                 JSON.stringify(ajv.errors),
         );
     }
+    catalogue.set(catalogueCopy);
 }
diff --git a/src/stores/options.ts b/src/stores/options.ts
index 613b399b..ea218afd 100644
--- a/src/stores/options.ts
+++ b/src/stores/options.ts
@@ -8,20 +8,22 @@ import optionsSchema from "../../schema/options.schema.json";
 export const lensOptions = writable<LensOptions | undefined>();
 
 /**
- * Set the options. A warning is logged to the browser console if the options do not match the JSON schema.
+ * Set the options. A warning is logged to the browser console if the options do not match the JSON schema. Note that the function makes a deep copy of the options so modifying the original object has no effect.
  */
-export function setOptions(options: LensOptions) {
-    lensOptions.set(options);
+export function setOptions(newOptions: LensOptions) {
+    // Make a copy to avoid modifying the original object
+    const optionsCopy = structuredClone(newOptions);
     const ajv = new Ajv({
         allErrors: true,
         removeAdditional: true,
     });
     addFormats(ajv);
-    const valid = ajv.validate(optionsSchema, options);
+    const valid = ajv.validate(optionsSchema, optionsCopy);
     if (!valid) {
         console.warn(
             "Options do not conform with JSON schema: " +
                 JSON.stringify(ajv.errors),
         );
     }
+    lensOptions.set(optionsCopy);
 }
diff --git a/src/stores/query.ts b/src/stores/query.ts
index 170d52b3..3d30415c 100644
--- a/src/stores/query.ts
+++ b/src/stores/query.ts
@@ -12,8 +12,11 @@ export function getQueryStore(): QueryItem[][] {
     return get(queryStore);
 }
 
+/**
+ * Set the query store. Note that the function makes a deep copy of the query store so modifying the original object has no effect.
+ */
 export function setQueryStore(query: QueryItem[][]): void {
-    queryStore.set(query);
+    queryStore.set(structuredClone(query));
 }
 
 /**
@@ -216,10 +219,10 @@ function findObjectsWithSameName(objectsArray: QueryItem[]): QueryItem[] {
 }
 
 /**
- * Adds an item to the currently active query group
+ * Adds an item to the currently active query group. Note that the function makes a deep copy of the query item so modifying the original object has no effect.
  * @param queryObject - the object to be added to the store
  */
 export const addItemToActiveQueryGroup = (queryObject: QueryItem): void => {
     const groupIndex = get(activeQueryGroupIndex);
-    addItemToQuery(queryObject, groupIndex);
+    addItemToQuery(structuredClone(queryObject), groupIndex);
 };