diff --git a/src/components/RightSidebar/RightSidebar.vue b/src/components/RightSidebar/RightSidebar.vue
index f835a00b73..f9ea932dfa 100644
--- a/src/components/RightSidebar/RightSidebar.vue
+++ b/src/components/RightSidebar/RightSidebar.vue
@@ -21,14 +21,33 @@
 -->
 
 <template>
-	<NcAppSidebar v-show="opened"
+	<NcAppSidebar v-if="token"
+		:open="opened"
 		:name="name"
 		:title="name"
 		:active="activeTab"
 		:class="'active-tab-' + activeTab"
+		:toggle-classes="{ 'chat-button-sidebar-toggle': isInCall }"
+		:toggle-attrs="isInCall ? inCallToggleAttrs : undefined"
+		@update:open="handleUpdateOpen"
 		@update:active="handleUpdateActive"
 		@closed="handleClosed"
 		@close="handleClose">
+		<!-- Use a custom icon when sidebar is used for chat messages during the call -->
+		<template #toggle-icon>
+			<template v-if="isInCall">
+				<MessageText :size="20" />
+				<NcCounterBubble v-if="unreadMessagesCounter > 0"
+					class="chat-button__unread-messages-counter"
+					:type="hasUnreadMentions ? 'highlighted' : 'outlined'">
+					{{ unreadMessagesCounter }}
+				</NcCounterBubble>
+			</template>
+			<template v-else>
+				<!-- Use the old icon on older versions -->
+				<MenuIcon :size="20" />
+			</template>
+		</template>
 		<template #description>
 			<LobbyStatus v-if="canFullModerate && hasLobbyEnabled" :token="token" />
 		</template>
@@ -106,13 +125,17 @@ import CogIcon from 'vue-material-design-icons/Cog.vue'
 import DotsCircle from 'vue-material-design-icons/DotsCircle.vue'
 import FolderMultipleImage from 'vue-material-design-icons/FolderMultipleImage.vue'
 import InformationOutline from 'vue-material-design-icons/InformationOutline.vue'
+import MenuIcon from 'vue-material-design-icons/Menu.vue'
 import Message from 'vue-material-design-icons/Message.vue'
+import MessageText from 'vue-material-design-icons/MessageText.vue'
 
+import { showMessage } from '@nextcloud/dialogs'
 import { emit, subscribe, unsubscribe } from '@nextcloud/event-bus'
 
 import NcAppSidebar from '@nextcloud/vue/dist/Components/NcAppSidebar.js'
 import NcAppSidebarTab from '@nextcloud/vue/dist/Components/NcAppSidebarTab.js'
 import NcButton from '@nextcloud/vue/dist/Components/NcButton.js'
+import NcCounterBubble from '@nextcloud/vue/dist/Components/NcCounterBubble.js'
 
 import BreakoutRoomsTab from './BreakoutRooms/BreakoutRoomsTab.vue'
 import LobbyStatus from './LobbyStatus.vue'
@@ -135,6 +158,7 @@ export default {
 		NcAppSidebar,
 		NcAppSidebarTab,
 		NcButton,
+		NcCounterBubble,
 		ParticipantsTab,
 		SetGuestUsername,
 		SharedItemsTab,
@@ -146,6 +170,8 @@ export default {
 		FolderMultipleImage,
 		InformationOutline,
 		Message,
+		MessageText,
+		MenuIcon,
 	},
 
 	mixins: [
@@ -163,6 +189,7 @@ export default {
 		return {
 			activeTab: 'participants',
 			contactsLoading: false,
+			unreadNotificationHandle: null,
 		}
 	},
 
@@ -171,7 +198,7 @@ export default {
 			return this.$store.getters.getSidebarStatus
 		},
 		opened() {
-			return !!this.token && !this.isInLobby && this.show
+			return !this.isInLobby && this.show
 		},
 		token() {
 			return this.$store.getters.getToken()
@@ -277,6 +304,21 @@ export default {
 		breakoutRoomsText() {
 			return t('spreed', 'Breakout rooms')
 		},
+
+		unreadMessagesCounter() {
+			return this.conversation.unreadMessages
+		},
+		hasUnreadMentions() {
+			return this.conversation.unreadMention
+		},
+
+		inCallToggleAttrs() {
+			return {
+				'data-theme-dark': true,
+				'aria-label': t('spreed', 'Open chat'),
+				title: t('spreed', 'Open chat')
+			}
+		},
 	},
 
 	watch: {
@@ -311,6 +353,27 @@ export default {
 			},
 		},
 
+		unreadMessagesCounter(newValue, oldValue) {
+			if (!this.isInCall || this.opened) {
+				return
+			}
+
+			// new messages arrived
+			if (newValue > 0 && oldValue === 0 && !this.hasUnreadMentions) {
+				this.notifyUnreadMessages(t('spreed', 'You have new unread messages in the chat.'))
+			}
+		},
+
+		hasUnreadMentions(newValue) {
+			if (!this.isInCall || this.opened) {
+				return
+			}
+
+			if (newValue) {
+				this.notifyUnreadMessages(t('spreed', 'You have been mentioned in the chat.'))
+			}
+		},
+
 		isInCall(newValue) {
 			if (newValue) {
 				// Set 'chat' tab as active, and switch to it if sidebar is open
@@ -318,6 +381,9 @@ export default {
 				return
 			}
 
+			// discard notification if the call ends
+			this.notifyUnreadMessages(null)
+
 			// If 'chat' tab wasn't active, leave it as is
 			if (this.activeTab !== 'chat') {
 				return
@@ -358,11 +424,28 @@ export default {
 	},
 
 	methods: {
+		openSidebar() {
+			// In call by default open on chat
+			if (this.isInCall) {
+				this.activeTab = 'chat'
+			}
+			this.$store.dispatch('showSidebar')
+			BrowserStorage.setItem('sidebarOpen', 'true')
+		},
+
 		handleClose() {
 			this.$store.dispatch('hideSidebar')
 			BrowserStorage.setItem('sidebarOpen', 'false')
 		},
 
+		handleUpdateOpen(open) {
+			if (open) {
+				this.openSidebar()
+			} else {
+				this.handleClose()
+			}
+		},
+
 		handleUpdateActive(active) {
 			this.activeTab = active
 		},
@@ -374,6 +457,21 @@ export default {
 		handleClosed() {
 			emit('files:sidebar:closed', {})
 		},
+
+		notifyUnreadMessages(message) {
+			if (this.unreadNotificationHandle) {
+				this.unreadNotificationHandle.hideToast()
+				this.unreadNotificationHandle = null
+			}
+			if (message) {
+				this.unreadNotificationHandle = showMessage(message, {
+					onClick: () => {
+						this.activeTab = 'chat'
+						this.openSidebar()
+					},
+				})
+			}
+		},
 	},
 }
 </script>
@@ -414,4 +512,26 @@ export default {
 	height: 100%;
 }
 
+.chat-button__unread-messages-counter {
+	position: absolute;
+	bottom: 2px;
+	right: 2px;
+	pointer-events: none;
+
+	&.counter-bubble__counter--highlighted {
+		color: var(--color-primary-text);
+	}
+}
+</style>
+
+<style lang="scss">
+/*
+ * NcAppSidebar toggle it rendered on the page outside the sidebar element, so we need global styles here.
+ * It is _quite_ safe, as chat-button-sidebar-toggle class is defined here manually, not an internal class.
+ */
+.chat-button-sidebar-toggle {
+	position: relative;
+	// Allow unread counter to overflow rounded button
+	overflow: visible !important;
+}
 </style>
diff --git a/src/components/TopBar/TopBar.vue b/src/components/TopBar/TopBar.vue
index 564312bcf8..6c8274ca2d 100644
--- a/src/components/TopBar/TopBar.vue
+++ b/src/components/TopBar/TopBar.vue
@@ -100,40 +100,6 @@
 
 		<CallButton class="top-bar__button" />
 
-		<!-- sidebar toggle -->
-		<template v-if="showOpenSidebarButton">
-			<!-- in chat: open last tab -->
-			<NcButton v-if="!isInCall"
-				:aria-label="t('spreed', 'Open sidebar')"
-				:title="t('spreed', 'Open sidebar')"
-				class="top-bar__button dark-hover"
-				close-after-click="true"
-				type="tertiary"
-				@click="openSidebar">
-				<template #icon>
-					<MenuIcon :size="20" />
-				</template>
-			</NcButton>
-
-			<!-- in call: open chat tab -->
-			<NcButton v-else
-				:aria-label="t('spreed', 'Open chat')"
-				:title="t('spreed', 'Open chat')"
-				class="top-bar__button chat-button dark-hover"
-				type="tertiary"
-				@click="openSidebar('chat')">
-				<template #icon>
-					<MessageText :size="20"
-						fill-color="#ffffff" />
-					<NcCounterBubble v-if="unreadMessagesCounter > 0"
-						class="chat-button__unread-messages-counter"
-						:type="hasUnreadMentions ? 'highlighted' : 'outlined'">
-						{{ unreadMessagesCounter }}
-					</NcCounterBubble>
-				</template>
-			</NcButton>
-		</template>
-
 		<!-- Breakout rooms editor -->
 		<BreakoutRoomsEditor v-if="showBreakoutRoomsEditor"
 			:token="token"
@@ -143,15 +109,11 @@
 
 <script>
 import AccountMultiple from 'vue-material-design-icons/AccountMultiple.vue'
-import MenuIcon from 'vue-material-design-icons/Menu.vue'
-import MessageText from 'vue-material-design-icons/MessageText.vue'
 
 import { getCapabilities } from '@nextcloud/capabilities'
-import { showMessage } from '@nextcloud/dialogs'
 import { emit } from '@nextcloud/event-bus'
 
 import NcButton from '@nextcloud/vue/dist/Components/NcButton.js'
-import NcCounterBubble from '@nextcloud/vue/dist/Components/NcCounterBubble.js'
 import Tooltip from '@nextcloud/vue/dist/Directives/Tooltip.js'
 import richEditor from '@nextcloud/vue/dist/Mixins/richEditor.js'
 
@@ -184,13 +146,10 @@ export default {
 		ConversationIcon,
 		TopBarMediaControls,
 		NcButton,
-		NcCounterBubble,
 		TopBarMenu,
 		ReactionMenu,
 		// Icons
 		AccountMultiple,
-		MenuIcon,
-		MessageText,
 	},
 
 	mixins: [
@@ -215,7 +174,6 @@ export default {
 
 	data: () => {
 		return {
-			unreadNotificationHandle: null,
 			showBreakoutRoomsEditor: false,
 			localCallParticipantModel,
 			localMediaModel,
@@ -227,10 +185,6 @@ export default {
 			return this.$store.getters.getMainContainerSelector()
 		},
 
-		showOpenSidebarButton() {
-			return !this.$store.getters.getSidebarStatus
-		},
-
 		isOneToOneConversation() {
 			return this.conversation.type === CONVERSATION.TYPE.ONE_TO_ONE
 		},
@@ -251,13 +205,6 @@ export default {
 			return getStatusMessage(this.conversation)
 		},
 
-		unreadMessagesCounter() {
-			return this.conversation.unreadMessages
-		},
-		hasUnreadMentions() {
-			return this.conversation.unreadMention
-		},
-
 		renderedDescription() {
 			return this.renderContent(this.conversation.description)
 		},
@@ -314,34 +261,6 @@ export default {
 	},
 
 	watch: {
-		unreadMessagesCounter(newValue, oldValue) {
-			if (!this.isInCall || !this.showOpenSidebarButton) {
-				return
-			}
-
-			// new messages arrived
-			if (newValue > 0 && oldValue === 0 && !this.hasUnreadMentions) {
-				this.notifyUnreadMessages(t('spreed', 'You have new unread messages in the chat.'))
-			}
-		},
-
-		hasUnreadMentions(newValue) {
-			if (!this.isInCall || !this.showOpenSidebarButton) {
-				return
-			}
-
-			if (newValue) {
-				this.notifyUnreadMessages(t('spreed', 'You have been mentioned in the chat.'))
-			}
-		},
-
-		isInCall(newValue) {
-			if (!newValue) {
-				// discard notification if the call ends
-				this.notifyUnreadMessages(null)
-			}
-		},
-
 		isOneToOneConversation: {
 			immediate: true,
 			// Group conversations have mixin in RightSidebar, so should work only for one-to-one
@@ -373,16 +292,6 @@ export default {
 	},
 
 	methods: {
-		notifyUnreadMessages(message) {
-			if (this.unreadNotificationHandle) {
-				this.unreadNotificationHandle.hideToast()
-				this.unreadNotificationHandle = null
-			}
-			if (message) {
-				this.unreadNotificationHandle = showMessage(message)
-			}
-		},
-
 		openSidebar(activeTab) {
 			if (typeof activeTab === 'string') {
 				emit('spreed:select-active-sidebar-tab', activeTab)
@@ -410,7 +319,9 @@ export default {
 	display: flex;
 	z-index: 10;
 	justify-content: flex-end;
-	padding: 8px;
+	padding: calc(2 * var(--default-grid-baseline));
+	// Reserve space for the sidebar toggle button
+	padding-right: calc(2 * var(--default-grid-baseline) + var(--app-sidebar-offset));
 	background-color: var(--color-main-background);
 	border-bottom: 1px solid var(--color-border);
 
@@ -454,18 +365,6 @@ export default {
 		}
 	}
 
-	.chat-button {
-		position: relative;
-		overflow: visible;
-		&__unread-messages-counter {
-			position: absolute;
-			top: 24px;
-			right: 2px;
-			pointer-events: none;
-			color: var(--color-primary-element);
-		}
-	}
-
 	&--authorised {
 		.conversation-icon {
 			margin-left: calc(var(--default-clickable-area) + var(--default-grid-baseline));