diff --git a/client/src/composables.ts b/client/src/composables.ts
index 54c968bc..32102146 100644
--- a/client/src/composables.ts
+++ b/client/src/composables.ts
@@ -47,6 +47,7 @@ import type {
 import { useQuery } from "@urql/vue";
 import dayjs from "dayjs";
 import { t } from "i18next";
+import { cloneDeep } from "lodash";
 import orderBy from "lodash/orderBy";
 import log from "loglevel";
 import type { ComputedRef, Ref } from "vue";
@@ -192,10 +193,12 @@ export function useCourseData(courseSlug: string) {
       log.error(result.error);
     }
 
-    course.value = result.data?.course as unknown as Course;
-    actionCompetences.value = result.data?.course
-      ?.action_competences as ActionCompetence[];
-    learningPath.value = result.data?.course?.learning_path as LearningPathType;
+    // VBV-757: clone data from `COURSE_QUERY` here, so that each user in
+    // `useCourseDataWithCompletion` has its own completion instance in the course
+    const courseData = cloneDeep(result.data?.course) as unknown as Course;
+    course.value = courseData;
+    actionCompetences.value = courseData.action_competences as ActionCompetence[];
+    learningPath.value = courseData.learning_path as LearningPathType;
 
     // attach circle information to learning contents
     if (learningPath.value) {
diff --git a/client/src/types.ts b/client/src/types.ts
index 93ed9552..a24f6ecb 100644
--- a/client/src/types.ts
+++ b/client/src/types.ts
@@ -204,6 +204,8 @@ export interface Course {
   slug: string;
   profiles: string[];
   configuration: CourseConfiguration;
+  learning_path?: LearningPathType;
+  action_competences?: ActionCompetence[];
 }
 
 export interface CourseCategory {