diff --git a/src/app/qml/FullScreenMap.qml b/src/app/qml/FullScreenMap.qml
index 0d2d9d566..53aa70228 100644
--- a/src/app/qml/FullScreenMap.qml
+++ b/src/app/qml/FullScreenMap.qml
@@ -59,7 +59,7 @@ ApplicationWindow {
 
         Connections {
             target: mapView.map
-            function onCopyrightLinkActivated() {
+            function onCopyrightLinkActivated(link: string): void {
                 Qt.openUrlExternally(link);
             }
         }
diff --git a/src/app/qml/Main.qml b/src/app/qml/Main.qml
index 177de6e6d..2a55158d5 100644
--- a/src/app/qml/Main.qml
+++ b/src/app/qml/Main.qml
@@ -60,21 +60,21 @@ Kirigami.ApplicationWindow {
 
     Connections {
         target: LoginHelper
-        function onLoaded() {
+        function onLoaded(): void {
             root.load();
         }
     }
 
     Connections {
         target: Registration
-        function onLoaded() {
+        function onLoaded(): void {
             root.load();
         }
     }
 
     Connections {
         target: root.quitAction
-        function onTriggered() {
+        function onTriggered(): void {
             Qt.quit();
         }
     }
@@ -98,7 +98,7 @@ Kirigami.ApplicationWindow {
     Connections {
         target: RoomManager
 
-        function onCurrentRoomChanged() {
+        function onCurrentRoomChanged(): void {
             if (RoomManager.currentRoom && pageStack.depth <= 1 && root.initialized && Kirigami.Settings.isMobile) {
                 let roomPage = pageStack.layers.push(Qt.createComponent('org.kde.neochat', 'RoomPage'));
                 roomPage.backRequested.connect(event => {
@@ -107,31 +107,31 @@ Kirigami.ApplicationWindow {
             }
         }
 
-        function onAskJoinRoom(room) {
+        function onAskJoinRoom(room: NeoChatRoom): void {
             Qt.createComponent("org.kde.neochat", "JoinRoomDialog").createObject(root, {
                 room: room,
                 connection: root.connection
             }).open();
         }
 
-        function onShowUserDetail(user, room) {
+        function onShowUserDetail(user, room: NeoChatRoom): void {
             root.showUserDetail(user, room);
         }
 
-        function goToEvent(event) {
+        function goToEvent(event: string): void {
             if (event.length > 0) {
                 roomItem.goToEvent(event);
             }
             roomItem.forceActiveFocus();
         }
 
-        function onAskDirectChatConfirmation(user) {
+        function onAskDirectChatConfirmation(user): void {
             Qt.createComponent("org.kde.neochat", "AskDirectChatConfirmation").createObject(this, {
                 user: user
             }).open();
         }
 
-        function onExternalUrl(url) {
+        function onExternalUrl(url): void {
             let dialog = Qt.createComponent("org.kde.neochat", "ConfirmUrlDialog").createObject(this);
             dialog.link = url;
             dialog.open();
diff --git a/src/app/qml/NeochatMaximizeComponent.qml b/src/app/qml/NeochatMaximizeComponent.qml
index e97b218fa..1e794103b 100644
--- a/src/app/qml/NeochatMaximizeComponent.qml
+++ b/src/app/qml/NeochatMaximizeComponent.qml
@@ -72,7 +72,7 @@ Components.AlbumMaximizeComponent {
 
     Connections {
         target: MediaManager
-        function onPlaybackStarted() {
+        function onPlaybackStarted(): void {
             if (currentItem.playbackState === MediaPlayer.PlayingState) {
                 currentItem.pause();
             }
@@ -82,7 +82,7 @@ Components.AlbumMaximizeComponent {
     Connections {
         target: currentRoom
 
-        function onFileTransferProgress(id, progress, total) {
+        function onFileTransferProgress(id: string, progress: int, total: int): void {
             if (id == root.currentEventId) {
                 root.downloadAction.progress = progress / total * 100.0;
             }
@@ -130,7 +130,7 @@ Components.AlbumMaximizeComponent {
 
     Connections {
         target: RoomManager
-        function onCloseFullScreen() {
+        function onCloseFullScreen(): void {
             root.close();
         }
     }
diff --git a/src/app/qml/QrScannerPage.qml b/src/app/qml/QrScannerPage.qml
index 1090cb912..a47ef58a6 100644
--- a/src/app/qml/QrScannerPage.qml
+++ b/src/app/qml/QrScannerPage.qml
@@ -22,7 +22,7 @@ Kirigami.Page {
 
     Connections {
         target: root.QQC2.ApplicationWindow.window
-        function onClosing() {
+        function onClosing(): void {
             root.destroy();
         }
     }
diff --git a/src/app/qml/RoomPage.qml b/src/app/qml/RoomPage.qml
index 49e506156..0e8da1d49 100644
--- a/src/app/qml/RoomPage.qml
+++ b/src/app/qml/RoomPage.qml
@@ -80,7 +80,7 @@ Kirigami.Page {
 
     Connections {
         target: root.currentRoom.connection
-        function onIsOnlineChanged() {
+        function onIsOnlineChanged(): void {
             if (!root.currentRoom.connection.isOnline) {
                 banner.text = i18nc("@info:status", "NeoChat is offline. Please check your network connection.");
                 banner.visible = true;
@@ -162,20 +162,20 @@ Kirigami.Page {
 
     Connections {
         target: RoomManager
-        function onCurrentRoomChanged() {
+        function onCurrentRoomChanged(): void {
             if (root.currentRoom && root.currentRoom.isInvite) {
                 Controller.clearInvitationNotification(root.currentRoom.id);
             }
         }
 
-        function onGoToEvent(eventId) {
+        function onGoToEvent(eventId: string): void {
             (timelineViewLoader.item as TimelineView).goToEvent(eventId);
         }
     }
 
     Connections {
         target: root.currentRoom.connection
-        function onJoinedRoom(room, invited) {
+        function onJoinedRoom(room: NeoChatRoom, invited: NeoChatRoom): void {
             if (root.currentRoom.id === invited.id) {
                 RoomManager.resolveResource(room.id);
             }
@@ -195,13 +195,13 @@ Kirigami.Page {
     Connections {
         target: RoomManager
 
-        function onShowMessage(messageType, message) {
+        function onShowMessage(messageType: Kirigami.MessageType, message: string): void {
             banner.text = message;
             banner.type = messageType;
             banner.visible = true;
         }
 
-        function onShowEventSource(eventId) {
+        function onShowEventSource(eventId: string): void {
             (root.Kirigami.PageStack.pageStack as Kirigami.PageRow).pushDialogLayer(Qt.createComponent('org.kde.neochat', 'MessageSourceSheet'), {
                 sourceText: root.currentRoom.getEventJsonSource(eventId)
             }, {
@@ -210,7 +210,7 @@ Kirigami.Page {
             });
         }
 
-        function onShowMessageMenu(eventId, author, messageComponentType, plainText, htmlText, selectedText, hoveredLink, isThread) {
+        function onShowMessageMenu(eventId: string, author, messageComponentType, plainText: string, htmlText: string, selectedText: string, hoveredLink: string, isThread: bool): void {
             const contextMenu = messageDelegateContextMenu.createObject(root, {
                 selectedText: selectedText,
                 hoveredLink: hoveredLink,
diff --git a/src/app/qml/ServerComboBox.qml b/src/app/qml/ServerComboBox.qml
index c8134e86c..ee06cc52a 100644
--- a/src/app/qml/ServerComboBox.qml
+++ b/src/app/qml/ServerComboBox.qml
@@ -177,7 +177,7 @@ QQC2.ComboBox {
 
                 Connections {
                     target: serverListModel
-                    function onServerCheckComplete(url, valid) {
+                    function onServerCheckComplete(url: string, valid: bool): void {
                         if (url == serverUrlField.text && valid) {
                             serverUrlField.isValidServer = true;
                         }
diff --git a/src/chatbar/EmojiDialog.qml b/src/chatbar/EmojiDialog.qml
index 3c0941e20..211cf8812 100644
--- a/src/chatbar/EmojiDialog.qml
+++ b/src/chatbar/EmojiDialog.qml
@@ -25,7 +25,7 @@ QQC2.Popup {
 
     Connections {
         target: RoomManager
-        function onCurrentRoomChanged() {
+        function onCurrentRoomChanged(): void {
             root.close();
         }
     }
diff --git a/src/chatbar/ImageEditorPage.qml b/src/chatbar/ImageEditorPage.qml
index af8b623df..a11cc4763 100644
--- a/src/chatbar/ImageEditorPage.qml
+++ b/src/chatbar/ImageEditorPage.qml
@@ -100,7 +100,7 @@ Kirigami.Page {
             }
             Connections {
                 target: selectionTool.selectionArea
-                function onDoubleClicked() {
+                function onDoubleClicked(): void {
                     rootEditorView.crop();
                 }
             }
diff --git a/src/login/Homeserver.qml b/src/login/Homeserver.qml
index 49e00d080..40631c7ef 100644
--- a/src/login/Homeserver.qml
+++ b/src/login/Homeserver.qml
@@ -39,7 +39,7 @@ LoginStep {
 
     Connections {
         target: Registration
-        function onConnected(connection): void {
+        function onConnected(connection: NeoChatConnection): void {
             root.processed("Loading");
         }
     }
diff --git a/src/login/Loading.qml b/src/login/Loading.qml
index f5a689e12..f7d7c5663 100644
--- a/src/login/Loading.qml
+++ b/src/login/Loading.qml
@@ -23,7 +23,7 @@ LoginStep {
 
     Connections {
         target: Controller
-        function onConnectionAdded(connection) {
+        function onConnectionAdded(connection: NeoChatConnection): void {
             connection.syncDone.connect(() => root.closeDialog());
         }
     }
diff --git a/src/login/Password.qml b/src/login/Password.qml
index 9bc9262ab..b326882e2 100644
--- a/src/login/Password.qml
+++ b/src/login/Password.qml
@@ -14,7 +14,7 @@ LoginStep {
 
     Connections {
         target: LoginHelper
-        function onConnected() {
+        function onConnected(): void {
             processed("Loading");
         }
     }
diff --git a/src/login/Sso.qml b/src/login/Sso.qml
index 5991f4e84..3506c646a 100644
--- a/src/login/Sso.qml
+++ b/src/login/Sso.qml
@@ -18,10 +18,10 @@ LoginStep {
 
     Connections {
         target: LoginHelper
-        function onSsoUrlChanged() {
+        function onSsoUrlChanged(): void {
             UrlHelper.openUrl(LoginHelper.ssoUrl);
         }
-        function onConnected() {
+        function onConnected(): void {
             processed("Loading");
         }
     }
diff --git a/src/login/WelcomePage.qml b/src/login/WelcomePage.qml
index 2d3481a09..759a0db29 100644
--- a/src/login/WelcomePage.qml
+++ b/src/login/WelcomePage.qml
@@ -214,7 +214,7 @@ Kirigami.Page {
                     Connections {
                         target: Registration
 
-                        function onNextStepChanged() {
+                        function onNextStepChanged(): void {
                             if (Registration.nextStep === "m.login.recaptcha") {
                                 stepConnections.onProcessed("Captcha");
                             }
@@ -232,7 +232,7 @@ Kirigami.Page {
                     Connections {
                         target: LoginHelper
 
-                        function onLoginErrorOccured(message) {
+                        function onLoginErrorOccured(message: string): void {
                             headerMessage.text = message;
                             headerMessage.visible = message.length > 0;
                             headerMessage.type = Kirigami.MessageType.Error;
diff --git a/src/messagecontent/AudioComponent.qml b/src/messagecontent/AudioComponent.qml
index 7c5cd614b..9be4917de 100644
--- a/src/messagecontent/AudioComponent.qml
+++ b/src/messagecontent/AudioComponent.qml
@@ -102,7 +102,7 @@ ColumnLayout {
 
     Connections {
         target: MediaManager
-        function onPlaybackStarted() {
+        function onPlaybackStarted(): void {
             if (audio.playbackState === MediaPlayer.PlayingState) {
                 audio.pause();
             }
diff --git a/src/messagecontent/LiveLocationComponent.qml b/src/messagecontent/LiveLocationComponent.qml
index c77a0a362..8e24a615b 100644
--- a/src/messagecontent/LiveLocationComponent.qml
+++ b/src/messagecontent/LiveLocationComponent.qml
@@ -70,7 +70,7 @@ ColumnLayout {
         }
         Connections {
             target: mapView.map
-            function onCopyrightLinkActivated() {
+            function onCopyrightLinkActivated(link: string): void {
                 Qt.openUrlExternally(link);
             }
         }
diff --git a/src/messagecontent/LocationComponent.qml b/src/messagecontent/LocationComponent.qml
index 89f9d6bb1..c2fc6205f 100644
--- a/src/messagecontent/LocationComponent.qml
+++ b/src/messagecontent/LocationComponent.qml
@@ -68,7 +68,7 @@ ColumnLayout {
 
         Connections {
             target: mapView.map
-            function onCopyrightLinkActivated(link: string) {
+            function onCopyrightLinkActivated(link: string): void {
                 Qt.openUrlExternally(link);
             }
         }
diff --git a/src/messagecontent/VideoComponent.qml b/src/messagecontent/VideoComponent.qml
index 7d6f39a58..c79746524 100644
--- a/src/messagecontent/VideoComponent.qml
+++ b/src/messagecontent/VideoComponent.qml
@@ -167,7 +167,7 @@ Video {
 
     Connections {
         target: MediaManager
-        function onPlaybackStarted() {
+        function onPlaybackStarted(): void {
             if (root.playbackState === MediaPlayer.PlayingState) {
                 root.pause();
             }
diff --git a/src/roominfo/LocationsPage.qml b/src/roominfo/LocationsPage.qml
index 149aeaf56..4638c6709 100644
--- a/src/roominfo/LocationsPage.qml
+++ b/src/roominfo/LocationsPage.qml
@@ -59,7 +59,7 @@ Kirigami.Page {
 
         Connections {
             target: mapView.map
-            function onCopyrightLinkActivated(link: string) {
+            function onCopyrightLinkActivated(link: string): void {
                 Qt.openUrlExternally(link);
             }
         }
diff --git a/src/roominfo/RoomDrawerPage.qml b/src/roominfo/RoomDrawerPage.qml
index 13b3f6ff5..5bf1a66af 100644
--- a/src/roominfo/RoomDrawerPage.qml
+++ b/src/roominfo/RoomDrawerPage.qml
@@ -102,7 +102,7 @@ Kirigami.Page {
 
     Connections {
         target: root.Kirigami.PageStack.pageStack
-        onWideModeChanged: {
+        function onWideModeChanged(): void {
             if ((root.Kirigami.PageStack.pageStack as Kirigami.PageRow).wideMode) {
                 root.Kirigami.PageStack.pop();
             }
diff --git a/src/rooms/RoomListPage.qml b/src/rooms/RoomListPage.qml
index 2ac211fd5..fdb6afed6 100644
--- a/src/rooms/RoomListPage.qml
+++ b/src/rooms/RoomListPage.qml
@@ -93,14 +93,14 @@ Kirigami.Page {
 
     Connections {
         target: RoomManager
-        function onCurrentSpaceChanged() {
+        function onCurrentSpaceChanged(): void {
             treeView.expandRecursively();
         }
     }
 
     Connections {
         target: RoomManager.sortFilterRoomTreeModel
-        function onCurrentRoomChanged() {
+        function onCurrentRoomChanged(): void {
             treeView.positionViewAtIndex(RoomManager.sortFilterRoomTreeModel.currentRoomIndex(), TableView.AlignVCenter)
         }
     }
@@ -197,7 +197,7 @@ Kirigami.Page {
                 Connections {
                     target: NeoChatConfig
 
-                    function onCompactRoomListChanged() {
+                    function onCompactRoomListChanged(): void {
                         treeView.collapseRecursively()
                         treeView.expandRecursively()
                     }
diff --git a/src/settings/AccountEditorPage.qml b/src/settings/AccountEditorPage.qml
index cf7febd58..cefabfa77 100644
--- a/src/settings/AccountEditorPage.qml
+++ b/src/settings/AccountEditorPage.qml
@@ -266,7 +266,7 @@ FormCard.FormCardPage {
 
     data: Connections {
         target: root.connection
-        function onPasswordStatus(status) {
+        function onPasswordStatus(status): void {
             if (status === NeoChatConnection.Success) {
                 confirmPassword.status = Kirigami.MessageType.Positive
                 confirmPassword.statusMessage = i18nc("@info", "Password changed successfully");
diff --git a/src/settings/AccountsPage.qml b/src/settings/AccountsPage.qml
index e858b041c..2d0e24f79 100644
--- a/src/settings/AccountsPage.qml
+++ b/src/settings/AccountsPage.qml
@@ -123,7 +123,7 @@ FormCard.FormCardPage {
 
     property Connections connections: Connections {
         target: Controller
-        function onConnectionAdded() {
+        function onConnectionAdded(): void {
             if (pageStack.layers.depth > 2) {
                 pageStack.layers.pop();
             }
diff --git a/src/settings/IgnoredUsersDialog.qml b/src/settings/IgnoredUsersDialog.qml
index 381cfda75..4a6f8ea7e 100644
--- a/src/settings/IgnoredUsersDialog.qml
+++ b/src/settings/IgnoredUsersDialog.qml
@@ -68,7 +68,7 @@ FormCard.FormCardPage {
 
     Connections {
         target: root.connection
-        function onIgnoredUsersListChanged() {
+        function onIgnoredUsersListChanged(): void {
             repeater.model = root.connection.ignoredUsers();
         }
     }
diff --git a/src/settings/RoomSecurityPage.qml b/src/settings/RoomSecurityPage.qml
index dd589af89..aeebdf590 100644
--- a/src/settings/RoomSecurityPage.qml
+++ b/src/settings/RoomSecurityPage.qml
@@ -180,7 +180,7 @@ FormCard.FormCardPage {
 
     property Connections connections: Connections {
         target: room
-        onEncryption: {
+        function onEncryption(): void {
             enableEncryptionSwitch.checked = room.usesEncryption;
         }
     }
diff --git a/src/settings/ThreePIdCard.qml b/src/settings/ThreePIdCard.qml
index e6caf910f..9596af3fe 100644
--- a/src/settings/ThreePIdCard.qml
+++ b/src/settings/ThreePIdCard.qml
@@ -138,7 +138,7 @@ ColumnLayout {
             Connections {
                 target: threePIdModel
 
-                function onModelReset() {
+                function onModelReset(): void {
                     newCountryCode.text = ""
                 }
             }
@@ -178,7 +178,7 @@ ColumnLayout {
             Connections {
                 target: threePIdModel
 
-                function onModelReset() {
+                function onModelReset(): void {
                     newId.text = ""
                 }
             }
diff --git a/src/timeline/TimelineView.qml b/src/timeline/TimelineView.qml
index 9902b6987..cb142a46a 100644
--- a/src/timeline/TimelineView.qml
+++ b/src/timeline/TimelineView.qml
@@ -149,27 +149,27 @@ QQC2.ScrollView {
         Connections {
             target: messageListView.model.sourceModel.timelineMessageModel
 
-            function onModelAboutToBeReset() {
+            function onModelAboutToBeReset(): void {
                 (root.QQC2.ApplicationWindow.window as Main).hoverLinkIndicator.text = "";
                 _private.hasScrolledUpBefore = false;
             }
 
-            function onModelResetComplete() {
+            function onModelResetComplete(): void {
                 messageListView.positionViewAtBeginning();
             }
 
-            function onReadMarkerAdded() {
+            function onReadMarkerAdded(): void {
                 if (root.markReadCondition == LibNeoChat.TimelineMarkReadCondition.EntryVisible && messageListView.allUnreadVisible()) {
                     _private.room.markAllMessagesAsRead();
                 }
             }
 
-            function onNewLocalUserEventAdded() {
+            function onNewLocalUserEventAdded(): void {
                 messageListView.positionViewAtBeginning();
                 _private.room.markAllMessagesAsRead();
             }
 
-            function onRoomAboutToChange(oldRoom, newRoom) {
+            function onRoomAboutToChange(oldRoom: NeoChatRoom, newRoom: NeoChatRoom): void {
                 if (root.markReadCondition == LibNeoChat.TimelineMarkReadCondition.Exit ||
                     (root.markReadCondition == LibNeoChat.TimelineMarkReadCondition.ExitVisible && messageListView.allUnreadVisible())
                 ) {
@@ -177,7 +177,7 @@ QQC2.ScrollView {
                 }
             }
 
-            function onRoomChanged(oldRoom, newRoom) {
+            function onRoomChanged(oldRoom: NeoChatRoom, newRoom: NeoChatRoom): void {
                 if (root.markReadCondition == LibNeoChat.TimelineMarkReadCondition.Entry) {
                     newRoom.markAllMessagesAsRead();
                 }