diff --git a/src/components/TheCollections/Calendar.vue b/src/components/TheCollections/Calendar.vue
index 239d3a87..1b96adf2 100644
--- a/src/components/TheCollections/Calendar.vue
+++ b/src/components/TheCollections/Calendar.vue
@@ -128,6 +128,10 @@ export default {
 			}
 		},
 
+		tasks: function() {
+			return Object.values(this.calendar.tasks)
+		},
+
 		inputString: function() {
 			return t('tasks', 'Add a task to "{calendar}"...', { calendar: this.calendar.displayName })
 		},
@@ -141,7 +145,6 @@ export default {
 			return n('tasks', '%n Completed Task', '%n Completed Tasks', this.completedCount(this.calendarId))
 		} },
 	mapGetters({
-		tasks: 'getTasksByRoute',
 		completedCount: 'getCalendarCountCompleted',
 		calendar: 'getCalendarByRoute'
 	})
diff --git a/src/models/task.js b/src/models/task.js
index 336862ed..232643a8 100644
--- a/src/models/task.js
+++ b/src/models/task.js
@@ -98,6 +98,16 @@ export default class Task {
 		return Array.isArray(data) ? data[0] : data
 	}
 
+	/**
+	 * Return the key
+	 *
+	 * @readonly
+	 * @memberof Task
+	 */
+	get key() {
+		return this.uid + '~' + this.calendar.id
+	}
+
 	/**
 	 * Return the url
 	 *
diff --git a/src/store/calendars.js b/src/store/calendars.js
index f8037ab7..3f4afe17 100644
--- a/src/store/calendars.js
+++ b/src/store/calendars.js
@@ -134,7 +134,7 @@ const getters = {
 	 */
 	getCalendarCountByCollectionId: (state, getters) => (calendarId, collectionId) => {
 		var calendar = getters.getCalendarById(calendarId)
-		var count = calendar.tasks.filter(task => {
+		var count = Object.values(calendar.tasks).filter(task => {
 			return isTaskInList(task, collectionId) && !task.related
 		}).length
 		return count
@@ -258,7 +258,15 @@ const mutations = {
 	appendTasksToCalendar(state, { calendar, tasks }) {
 		calendar = state.calendars.find(search => search === calendar)
 
-		Vue.set(calendar, 'tasks', tasks)
+		// convert list into an array and remove duplicate
+		calendar.tasks = tasks.reduce((list, task) => {
+			if (list[task.uid]) {
+				console.debug('Duplicate task overridden', list[task.uid], task)
+			}
+			Vue.set(list, task.uid, task)
+			return list
+		}, calendar.tasks)
+
 	},
 
 	/**
@@ -447,7 +455,7 @@ const actions = {
 					return task
 				})
 				context.commit('appendTasksToCalendar', { calendar, tasks })
-				// context.commit('appendTasks', tasks)
+				context.commit('appendTasks', tasks)
 				return tasks
 			})
 			.catch((error) => {
diff --git a/src/store/collections.js b/src/store/collections.js
index 23b2367c..47db8efa 100644
--- a/src/store/collections.js
+++ b/src/store/collections.js
@@ -51,7 +51,7 @@ const getters = {
 	getCollectionCount: (state, getters, rootState) => (collectionId) => {
 		var count = 0
 		rootState.calendars.calendars.forEach(calendar => {
-			count += calendar.tasks.filter(task => {
+			count += Object.values(calendar.tasks).filter(task => {
 				return isTaskInList(task, collectionId) && !task.related
 			}).length
 		})
diff --git a/src/store/tasks.js b/src/store/tasks.js
index 00705b1b..a4073700 100644
--- a/src/store/tasks.js
+++ b/src/store/tasks.js
@@ -22,9 +22,14 @@
 
 import Vue from 'vue'
 import Vuex from 'vuex'
+import Task from '../models/task'
 
 Vue.use(Vuex)
 
+const state = {
+	tasks: {}
+}
+
 const getters = {
 	/**
 	 * Returns all tasks corresponding to the calendar
@@ -83,14 +88,14 @@ const getters = {
 			if (!calendar) {
 				return null
 			}
-			return calendar.tasks.find(task => {
+			return Object.values(calendar.tasks).find(task => {
 				return task.uri === rootState.route.params.taskId
 			})
 		}
 		// Else, we have to search all calendars
 		var task
 		for (let calendar of rootState.calendars.calendars) {
-			task = calendar.tasks.find(task => {
+			task = Object.values(calendar.tasks).find(task => {
 				return task.uri === rootState.route.params.taskId
 			})
 			if (task) return task
@@ -99,6 +104,24 @@ const getters = {
 }
 
 const mutations = {
+
+	/**
+	 * Store tasks into state
+	 *
+	 * @param {Object} state Default state
+	 * @param {Array<Task>} tasks Tasks
+	 */
+	appendTasks(state, tasks = []) {
+		state.tasks = tasks.reduce(function(list, task) {
+			if (task instanceof Task) {
+				Vue.set(list, task.key, task)
+			} else {
+				console.error('Wrong task object', task)
+			}
+			return list
+		}, state.tasks)
+	},
+
 	/**
 	 * Deletes a task
 	 *
@@ -186,4 +209,4 @@ const actions = {
 	}
 }
 
-export default { getters, mutations, actions }
+export default { state, getters, mutations, actions }