see below (had to delete some other changes

src/main/webapp/app/exercise/exercise-details/exercise-details.component.html

@@ -137,7 +137,7 @@
                 <div class="modal-footer">
                     <button type="button" class="btn btn-outline-secondary" data-dismiss="modal"
                         jhiTranslate="exercise.close"></button>
-                    <button class="btn"><fa-icon icon="heart"></fa-icon></button>
+                    <!-- <button class="btn"><fa-icon icon="heart"></fa-icon></button> -->
                 </div>
             </div>
         </div>