diff --git a/package.json b/package.json
index bf7a093494..bae4676cb3 100644
--- a/package.json
+++ b/package.json
@@ -62,7 +62,7 @@
         "@babel/runtime": "^7.12.5",
         "@matrix-org/analytics-events": "^0.5.0",
         "@matrix-org/matrix-wysiwyg": "^2.0.0",
-        "@matrix-org/react-sdk-module-api": "^0.0.4",
+        "@matrix-org/react-sdk-module-api": "^0.0.5",
         "@sentry/browser": "^7.0.0",
         "@sentry/tracing": "^7.0.0",
         "@testing-library/react-hooks": "^8.0.1",
diff --git a/src/LegacyCallHandler.tsx b/src/LegacyCallHandler.tsx
index 0fd8a7f5b9..a592c3b055 100644
--- a/src/LegacyCallHandler.tsx
+++ b/src/LegacyCallHandler.tsx
@@ -711,8 +711,8 @@ export default class LegacyCallHandler extends EventEmitter {
                     // Don't show a modal when we got rejected/the call was hung up
                     if (!hangupReason || [CallErrorCode.UserHangup, "user hangup"].includes(hangupReason)) break;
 
-                    let title;
-                    let description;
+                    let title: string;
+                    let description: string;
                     // TODO: We should either do away with these or figure out a copy for each code (expect user_hangup...)
                     if (call.hangupReason === CallErrorCode.UserBusy) {
                         title = _t("User Busy");
@@ -1094,16 +1094,17 @@ export default class LegacyCallHandler extends EventEmitter {
         }
 
         const roomId = await ensureDMExists(MatrixClientPeg.get(), nativeUserId);
-
-        if (isNotNull(roomId)) {
-            dis.dispatch<ViewRoomPayload>({
-                action: Action.ViewRoom,
-                room_id: roomId,
-                metricsTrigger: "WebDialPad",
-            });
-
-            await this.placeMatrixCall(roomId, CallType.Voice, transferee);
+        if (!roomId) {
+            throw new Error("Failed to ensure DM exists for dialing number");
         }
+
+        dis.dispatch<ViewRoomPayload>({
+            action: Action.ViewRoom,
+            room_id: roomId,
+            metricsTrigger: "WebDialPad",
+        });
+
+        await this.placeMatrixCall(roomId, CallType.Voice, transferee);
     }
 
     public async startTransferToPhoneNumber(
diff --git a/src/Notifier.ts b/src/Notifier.ts
index 52983f6fc3..d47a9c871b 100644
--- a/src/Notifier.ts
+++ b/src/Notifier.ts
@@ -197,8 +197,14 @@ class NotifierClass {
 
         // Ideally in here we could use MSC1310 to detect the type of file, and reject it.
 
+        const url = mediaFromMxc(content.url).srcHttp;
+        if (!url) {
+            logger.warn("Something went wrong when generating src http url for mxc");
+            return null;
+        }
+
         return {
-            url: mediaFromMxc(content.url).srcHttp,
+            url,
             name: content.name,
             type: content.type,
             size: content.size,
diff --git a/src/actions/RoomListActions.ts b/src/actions/RoomListActions.ts
index 6f8f944ab9..d8355e0a37 100644
--- a/src/actions/RoomListActions.ts
+++ b/src/actions/RoomListActions.ts
@@ -53,7 +53,7 @@ export default class RoomListActions {
         newTag: TagID | null,
         newIndex: number,
     ): AsyncActionPayload {
-        let metaData: Parameters<MatrixClient["setRoomTag"]>[2] | null = null;
+        let metaData: Parameters<MatrixClient["setRoomTag"]>[2] | undefined;
 
         // Is the tag ordered manually?
         const store = RoomListStore.instance;
@@ -113,10 +113,6 @@ export default class RoomListActions {
 
                 // if we moved lists or the ordering changed, add the new tag
                 if (newTag && newTag !== DefaultTagID.DM && (hasChangedSubLists || metaData)) {
-                    // metaData is the body of the PUT to set the tag, so it must
-                    // at least be an empty object.
-                    metaData = metaData || ({} as typeof metaData);
-
                     const promiseToAdd = matrixClient.setRoomTag(roomId, newTag, metaData).catch(function (err) {
                         logger.error("Failed to add tag " + newTag + " to room: " + err);
                         Modal.createDialog(ErrorDialog, {
diff --git a/src/components/structures/FilePanel.tsx b/src/components/structures/FilePanel.tsx
index ba5a68d333..ab7dd8ba5d 100644
--- a/src/components/structures/FilePanel.tsx
+++ b/src/components/structures/FilePanel.tsx
@@ -71,7 +71,7 @@ class FilePanel extends React.Component<IProps, IState> {
         removed: boolean,
         data: IRoomTimelineData,
     ): void => {
-        if (room?.roomId !== this.props?.roomId) return;
+        if (room?.roomId !== this.props.roomId) return;
         if (toStartOfTimeline || !data || !data.liveEvent || ev.isRedacted()) return;
 
         const client = MatrixClientPeg.get();
diff --git a/src/components/structures/MatrixChat.tsx b/src/components/structures/MatrixChat.tsx
index 4a58c66a35..cdecf9f61e 100644
--- a/src/components/structures/MatrixChat.tsx
+++ b/src/components/structures/MatrixChat.tsx
@@ -164,7 +164,7 @@ interface IProps {
     onNewScreen: (screen: string, replaceLast: boolean) => void;
     enableGuest?: boolean;
     // the queryParams extracted from the [real] query-string of the URI
-    realQueryParams?: QueryDict;
+    realQueryParams: QueryDict;
     // the initial queryParams extracted from the hash-fragment of the URI
     startingFragmentQueryParams?: QueryDict;
     // called when we have completed a token login
diff --git a/src/components/structures/RightPanel.tsx b/src/components/structures/RightPanel.tsx
index d4ebb198bf..b918c2c0c6 100644
--- a/src/components/structures/RightPanel.tsx
+++ b/src/components/structures/RightPanel.tsx
@@ -97,7 +97,7 @@ export default class RightPanel extends React.Component<IProps, IState> {
 
         return {
             cardState: currentCard?.state,
-            phase: currentCard?.phase,
+            phase: currentCard?.phase ?? undefined,
         };
     }
 
@@ -111,7 +111,7 @@ export default class RightPanel extends React.Component<IProps, IState> {
             this.delayedUpdate();
         } else if (
             this.state.phase === RightPanelPhases.RoomMemberInfo &&
-            member.userId === this.state.cardState.member?.userId
+            member.userId === this.state.cardState?.member?.userId
         ) {
             // refresh the member info (e.g. new power level)
             this.delayedUpdate();
@@ -156,7 +156,7 @@ export default class RightPanel extends React.Component<IProps, IState> {
         const cardState = this.props.overwriteCard?.state ?? this.state.cardState;
         switch (phase) {
             case RightPanelPhases.RoomMemberList:
-                if (roomId) {
+                if (!!roomId) {
                     card = (
                         <MemberList
                             roomId={roomId}
@@ -199,7 +199,9 @@ export default class RightPanel extends React.Component<IProps, IState> {
             }
             case RightPanelPhases.Room3pidMemberInfo:
             case RightPanelPhases.Space3pidMemberInfo:
-                card = <ThirdPartyMemberInfo event={cardState?.memberInfoEvent} key={roomId} />;
+                if (!!cardState?.memberInfoEvent) {
+                    card = <ThirdPartyMemberInfo event={cardState.memberInfoEvent} key={roomId} />;
+                }
                 break;
 
             case RightPanelPhases.NotificationPanel:
@@ -207,7 +209,7 @@ export default class RightPanel extends React.Component<IProps, IState> {
                 break;
 
             case RightPanelPhases.PinnedMessages:
-                if (this.props.room && SettingsStore.getValue("feature_pinning")) {
+                if (!!this.props.room && SettingsStore.getValue("feature_pinning")) {
                     card = (
                         <PinnedMessagesCard
                             room={this.props.room}
@@ -218,7 +220,7 @@ export default class RightPanel extends React.Component<IProps, IState> {
                 }
                 break;
             case RightPanelPhases.Timeline:
-                if (this.props.room) {
+                if (!!this.props.room) {
                     card = (
                         <TimelineCard
                             classNames="mx_ThreadPanel mx_TimelineCard"
@@ -233,20 +235,24 @@ export default class RightPanel extends React.Component<IProps, IState> {
                 }
                 break;
             case RightPanelPhases.FilePanel:
-                card = <FilePanel roomId={roomId} resizeNotifier={this.props.resizeNotifier} onClose={this.onClose} />;
+                if (!!roomId) {
+                    card = (
+                        <FilePanel roomId={roomId} resizeNotifier={this.props.resizeNotifier} onClose={this.onClose} />
+                    );
+                }
                 break;
 
             case RightPanelPhases.ThreadView:
-                if (this.props.room) {
+                if (!!this.props.room && !!cardState?.threadHeadEvent) {
                     card = (
                         <ThreadView
                             room={this.props.room}
                             resizeNotifier={this.props.resizeNotifier}
                             onClose={this.onClose}
-                            mxEvent={cardState?.threadHeadEvent}
-                            initialEvent={cardState?.initialEvent}
-                            isInitialEventHighlighted={cardState?.isInitialEventHighlighted}
-                            initialEventScrollIntoView={cardState?.initialEventScrollIntoView}
+                            mxEvent={cardState.threadHeadEvent}
+                            initialEvent={cardState.initialEvent}
+                            isInitialEventHighlighted={cardState.isInitialEventHighlighted}
+                            initialEventScrollIntoView={cardState.initialEventScrollIntoView}
                             permalinkCreator={this.props.permalinkCreator}
                             e2eStatus={this.props.e2eStatus}
                         />
@@ -255,18 +261,20 @@ export default class RightPanel extends React.Component<IProps, IState> {
                 break;
 
             case RightPanelPhases.ThreadPanel:
-                card = (
-                    <ThreadPanel
-                        roomId={roomId}
-                        resizeNotifier={this.props.resizeNotifier}
-                        onClose={this.onClose}
-                        permalinkCreator={this.props.permalinkCreator}
-                    />
-                );
+                if (!!roomId) {
+                    card = (
+                        <ThreadPanel
+                            roomId={roomId}
+                            resizeNotifier={this.props.resizeNotifier}
+                            onClose={this.onClose}
+                            permalinkCreator={this.props.permalinkCreator}
+                        />
+                    );
+                }
                 break;
 
             case RightPanelPhases.RoomSummary:
-                if (this.props.room) {
+                if (!!this.props.room) {
                     card = (
                         <RoomSummaryCard
                             room={this.props.room}
@@ -279,8 +287,8 @@ export default class RightPanel extends React.Component<IProps, IState> {
                 break;
 
             case RightPanelPhases.Widget:
-                if (this.props.room) {
-                    card = <WidgetCard room={this.props.room} widgetId={cardState?.widgetId} onClose={this.onClose} />;
+                if (!!this.props.room && !!cardState?.widgetId) {
+                    card = <WidgetCard room={this.props.room} widgetId={cardState.widgetId} onClose={this.onClose} />;
                 }
                 break;
         }
diff --git a/src/components/structures/RoomView.tsx b/src/components/structures/RoomView.tsx
index b121bdb5cc..c11892d22c 100644
--- a/src/components/structures/RoomView.tsx
+++ b/src/components/structures/RoomView.tsx
@@ -626,7 +626,7 @@ export class RoomView extends React.Component<IRoomProps, IRoomState> {
             wasContextSwitch: this.context.roomViewStore.getWasContextSwitch(),
             mainSplitContentType: room ? this.getMainSplitContentType(room) : undefined,
             initialEventId: undefined, // default to clearing this, will get set later in the method if needed
-            showRightPanel: this.context.rightPanelStore.isOpenForRoom(roomId),
+            showRightPanel: roomId ? this.context.rightPanelStore.isOpenForRoom(roomId) : false,
             activeCall: roomId ? CallStore.instance.getActiveCall(roomId) : null,
         };
 
@@ -662,7 +662,7 @@ export class RoomView extends React.Component<IRoomProps, IRoomState> {
             newState.initialEventPixelOffset = undefined;
 
             const thread = initialEvent?.getThread();
-            if (thread && !initialEvent?.isThreadRoot) {
+            if (thread?.rootEvent && !initialEvent?.isThreadRoot) {
                 dis.dispatch<ShowThreadPayload>({
                     action: Action.ShowThread,
                     rootEvent: thread.rootEvent,
@@ -675,7 +675,7 @@ export class RoomView extends React.Component<IRoomProps, IRoomState> {
                 newState.isInitialEventHighlighted = this.context.roomViewStore.isInitialEventHighlighted();
                 newState.initialEventScrollIntoView = this.context.roomViewStore.initialEventScrollIntoView();
 
-                if (thread && initialEvent?.isThreadRoot) {
+                if (thread?.rootEvent && initialEvent?.isThreadRoot) {
                     dis.dispatch<ShowThreadPayload>({
                         action: Action.ShowThread,
                         rootEvent: thread.rootEvent,
@@ -1016,7 +1016,7 @@ export class RoomView extends React.Component<IRoomProps, IRoomState> {
 
     private onRightPanelStoreUpdate = (): void => {
         this.setState({
-            showRightPanel: this.context.rightPanelStore.isOpenForRoom(this.state.roomId),
+            showRightPanel: this.state.roomId ? this.context.rightPanelStore.isOpenForRoom(this.state.roomId) : false,
         });
     };
 
@@ -1087,7 +1087,7 @@ export class RoomView extends React.Component<IRoomProps, IRoomState> {
             case "picture_snapshot":
                 ContentMessages.sharedInstance().sendContentListToRoom(
                     [payload.file],
-                    this.state.room.roomId,
+                    this.getRoomId(),
                     undefined,
                     this.context.client,
                 );
@@ -1496,6 +1496,7 @@ export class RoomView extends React.Component<IRoomProps, IRoomState> {
     );
 
     private checkDesktopNotifications(): void {
+        if (!this.state.room) return;
         const memberCount = this.state.room.getJoinedMemberCount() + this.state.room.getInvitedMemberCount();
         // if they are not alone prompt the user about notifications so they don't miss replies
         if (memberCount > 1 && Notifier.shouldShowPrompt()) {
@@ -1518,7 +1519,7 @@ export class RoomView extends React.Component<IRoomProps, IRoomState> {
         // open the room inviter
         dis.dispatch({
             action: "view_invite",
-            roomId: this.state.room.roomId,
+            roomId: this.getRoomId(),
         });
     };
 
@@ -1588,7 +1589,7 @@ export class RoomView extends React.Component<IRoomProps, IRoomState> {
             debuglog("Removing scroll_into_view flag from initial event");
             dis.dispatch<ViewRoomPayload>({
                 action: Action.ViewRoom,
-                room_id: this.state.room.roomId,
+                room_id: this.getRoomId(),
                 event_id: this.state.initialEventId,
                 highlighted: this.state.isInitialEventHighlighted,
                 scroll_into_view: false,
@@ -1606,7 +1607,7 @@ export class RoomView extends React.Component<IRoomProps, IRoomState> {
         }
 
         ContentMessages.sharedInstance()
-            .sendStickerContentToRoom(url, this.state.room.roomId, threadId, info, text, this.context.client)
+            .sendStickerContentToRoom(url, this.getRoomId(), threadId, info, text, this.context.client)
             .then(undefined, (error) => {
                 if (error.name === "UnknownDeviceError") {
                     // Let the staus bar handle this
@@ -1616,7 +1617,7 @@ export class RoomView extends React.Component<IRoomProps, IRoomState> {
     }
 
     private onSearch = (term: string, scope: SearchScope): void => {
-        const roomId = scope === SearchScope.Room ? this.state.room.roomId : undefined;
+        const roomId = scope === SearchScope.Room ? this.getRoomId() : undefined;
         debuglog("sending search request");
         const abortController = new AbortController();
         const promise = eventSearch(term, roomId, abortController.signal);
@@ -1655,7 +1656,7 @@ export class RoomView extends React.Component<IRoomProps, IRoomState> {
     private onForgetClick = (): void => {
         dis.dispatch({
             action: "forget_room",
-            room_id: this.state.room.roomId,
+            room_id: this.getRoomId(),
         });
     };
 
@@ -1663,7 +1664,7 @@ export class RoomView extends React.Component<IRoomProps, IRoomState> {
         this.setState({
             rejecting: true,
         });
-        this.context.client?.leave(this.state.roomId).then(
+        this.context.client?.leave(this.getRoomId()).then(
             () => {
                 dis.dispatch({ action: Action.ViewHomePage });
                 this.setState({
@@ -1757,7 +1758,7 @@ export class RoomView extends React.Component<IRoomProps, IRoomState> {
             // jumping to the bottom
             dis.dispatch<ViewRoomPayload>({
                 action: Action.ViewRoom,
-                room_id: this.state.room.roomId,
+                room_id: this.getRoomId(),
                 metricsTrigger: undefined, // room doesn't change
             });
         } else {
@@ -1903,7 +1904,7 @@ export class RoomView extends React.Component<IRoomProps, IRoomState> {
     private onFileDrop = (dataTransfer: DataTransfer): Promise<void> =>
         ContentMessages.sharedInstance().sendContentListToRoom(
             Array.from(dataTransfer.files),
-            this.state.room?.roomId ?? this.state.roomId,
+            this.getRoomId(),
             null,
             this.context.client,
             TimelineRenderingType.Room,
@@ -1921,7 +1922,8 @@ export class RoomView extends React.Component<IRoomProps, IRoomState> {
         return this.getPermalinkCreatorForRoom(this.state.room);
     }
 
-    private renderLocalRoomCreateLoader(localRoom: LocalRoom): ReactElement {
+    private renderLocalRoomCreateLoader(localRoom: LocalRoom): ReactNode {
+        if (!this.state.room || !this.context?.client) return null;
         const names = this.state.room.getDefaultRoomName(this.context.client.getSafeUserId());
         return (
             <RoomContext.Provider value={this.state}>
@@ -1930,7 +1932,7 @@ export class RoomView extends React.Component<IRoomProps, IRoomState> {
         );
     }
 
-    private renderLocalRoomView(localRoom: LocalRoom): ReactElement {
+    private renderLocalRoomView(localRoom: LocalRoom): ReactNode {
         return (
             <RoomContext.Provider value={this.state}>
                 <LocalRoomView
@@ -1944,7 +1946,7 @@ export class RoomView extends React.Component<IRoomProps, IRoomState> {
         );
     }
 
-    private renderWaitingForThirdPartyRoomView(inviteEvent: MatrixEvent): ReactElement {
+    private renderWaitingForThirdPartyRoomView(inviteEvent: MatrixEvent): ReactNode {
         return (
             <RoomContext.Provider value={this.state}>
                 <WaitingForThirdPartyRoomView
@@ -1956,7 +1958,7 @@ export class RoomView extends React.Component<IRoomProps, IRoomState> {
         );
     }
 
-    public render(): React.ReactNode {
+    public render(): ReactNode {
         if (!this.context.client) return null;
 
         if (this.state.room instanceof LocalRoom) {
diff --git a/src/components/structures/TimelinePanel.tsx b/src/components/structures/TimelinePanel.tsx
index 6172d6228a..874d0b7a34 100644
--- a/src/components/structures/TimelinePanel.tsx
+++ b/src/components/structures/TimelinePanel.tsx
@@ -1023,7 +1023,7 @@ class TimelinePanel extends React.Component<IProps, IState> {
             shouldSendRR &&
             // Only send a RR if the last read event is ahead in the timeline relative to
             // the current RR event.
-            lastReadEventIndex > currentRREventIndex &&
+            lastReadEventIndex! > currentRREventIndex! &&
             // Only send a RR if the last RR set != the one we would send
             this.lastRRSentEventId !== lastReadEvent?.getId();
 
@@ -1307,7 +1307,7 @@ class TimelinePanel extends React.Component<IProps, IState> {
         const pos = this.getReadMarkerPosition();
         const ret =
             this.state.readMarkerEventId !== null && // 1.
-            (pos < 0 || pos === null); // 3., 4.
+            (pos === null || pos < 0); // 3., 4.
         return ret;
     };
 
@@ -1351,7 +1351,7 @@ class TimelinePanel extends React.Component<IProps, IState> {
                     "TimelinePanel scrolling to eventId " +
                         eventId +
                         " at position " +
-                        offsetBase * 100 +
+                        offsetBase! * 100 +
                         "% + " +
                         pixelOffset,
                 );
diff --git a/src/components/views/messages/MessageActionBar.tsx b/src/components/views/messages/MessageActionBar.tsx
index 3a85406c4f..78d001ae95 100644
--- a/src/components/views/messages/MessageActionBar.tsx
+++ b/src/components/views/messages/MessageActionBar.tsx
@@ -64,7 +64,7 @@ interface IOptionsButtonProps {
     // TODO: Types
     getTile: () => any | null;
     getReplyChain: () => ReplyChain | null;
-    permalinkCreator: RoomPermalinkCreator;
+    permalinkCreator?: RoomPermalinkCreator;
     onFocusChange: (menuDisplayed: boolean) => void;
     getRelationsForEvent?: GetRelationsForEvent;
 }
@@ -208,10 +208,11 @@ const ReplyInThreadButton: React.FC<IReplyInThreadButton> = ({ mxEvent }) => {
         e.preventDefault();
         e.stopPropagation();
 
-        if (mxEvent.getThread() && !mxEvent.isThreadRoot) {
+        const thread = mxEvent.getThread();
+        if (thread?.rootEvent && !mxEvent.isThreadRoot) {
             defaultDispatcher.dispatch<ShowThreadPayload>({
                 action: Action.ShowThread,
-                rootEvent: mxEvent.getThread()!.rootEvent,
+                rootEvent: thread.rootEvent,
                 initialEvent: mxEvent,
                 scroll_into_view: true,
                 highlighted: true,
diff --git a/src/components/views/rooms/EventTile.tsx b/src/components/views/rooms/EventTile.tsx
index 38a9f29e84..925611ab80 100644
--- a/src/components/views/rooms/EventTile.tsx
+++ b/src/components/views/rooms/EventTile.tsx
@@ -576,6 +576,12 @@ export class UnwrappedEventTile extends React.Component<EventTileProps, IState>
 
         const encryptionInfo = MatrixClientPeg.get().getEventEncryptionInfo(mxEvent);
         const senderId = mxEvent.getSender();
+        if (!senderId) {
+            // something definitely wrong is going on here
+            this.setState({ verified: E2EState.Warning });
+            return;
+        }
+
         const userTrust = MatrixClientPeg.get().checkUserTrust(senderId);
 
         if (encryptionInfo.mismatchedSender) {
diff --git a/src/components/views/spaces/SpacePublicShare.tsx b/src/components/views/spaces/SpacePublicShare.tsx
index 68bf940831..af29169791 100644
--- a/src/components/views/spaces/SpacePublicShare.tsx
+++ b/src/components/views/spaces/SpacePublicShare.tsx
@@ -55,7 +55,7 @@ const SpacePublicShare: React.FC<IProps> = ({ space, onFinished }) => {
                 {_t("Share invite link")}
                 <span>{copiedText}</span>
             </AccessibleButton>
-            {space.canInvite(MatrixClientPeg.get()?.getUserId()) && shouldShowComponent(UIComponent.InviteUsers) ? (
+            {space.canInvite(MatrixClientPeg.get()?.getSafeUserId()) && shouldShowComponent(UIComponent.InviteUsers) ? (
                 <AccessibleButton
                     className="mx_SpacePublicShare_inviteButton"
                     onClick={() => {
diff --git a/src/hooks/useRoomNotificationState.ts b/src/hooks/useRoomNotificationState.ts
index 0f60288d66..cd29023eb1 100644
--- a/src/hooks/useRoomNotificationState.ts
+++ b/src/hooks/useRoomNotificationState.ts
@@ -23,11 +23,13 @@ import { PROPERTY_UPDATED } from "../stores/local-echo/GenericEchoChamber";
 import { CachedRoomKey } from "../stores/local-echo/RoomEchoChamber";
 import { useEventEmitter } from "./useEventEmitter";
 
-export const useNotificationState = (room: Room): [RoomNotifState, (state: RoomNotifState) => void] => {
+export const useNotificationState = (room: Room): [RoomNotifState | undefined, (state: RoomNotifState) => void] => {
     const echoChamber = useMemo(() => EchoChamber.forRoom(room), [room]);
-    const [notificationState, setNotificationState] = useState<RoomNotifState>(echoChamber.notificationVolume);
+    const [notificationState, setNotificationState] = useState<RoomNotifState | undefined>(
+        echoChamber.notificationVolume,
+    );
     useEventEmitter(echoChamber, PROPERTY_UPDATED, (key: CachedRoomKey) => {
-        if (key === CachedRoomKey.NotificationVolume) {
+        if (key === CachedRoomKey.NotificationVolume && echoChamber.notificationVolume !== undefined) {
             setNotificationState(echoChamber.notificationVolume);
         }
     });
diff --git a/src/linkify-matrix.ts b/src/linkify-matrix.ts
index 45fa06779e..f48bbe1514 100644
--- a/src/linkify-matrix.ts
+++ b/src/linkify-matrix.ts
@@ -191,12 +191,12 @@ export const options: Opts = {
         return {};
     },
 
-    formatHref: function (href: string, type: Type | string): string | null {
+    formatHref: function (href: string, type: Type | string): string {
         switch (type) {
             case Type.RoomAlias:
             case Type.UserId:
             default: {
-                return tryTransformEntityToPermalink(href);
+                return tryTransformEntityToPermalink(href) ?? "";
             }
         }
     },
@@ -209,7 +209,7 @@ export const options: Opts = {
 
     className: "linkified",
 
-    target: function (href: string, type: Type | string): string | null {
+    target: function (href: string, type: Type | string): string {
         if (type === Type.URL) {
             try {
                 const transformed = tryTransformPermalinkToLocalHref(href);
@@ -217,7 +217,7 @@ export const options: Opts = {
                     transformed !== href || // if it could be converted to handle locally for matrix symbols e.g. @user:server.tdl and matrix.to
                     decodeURIComponent(href).match(ELEMENT_URL_PATTERN) // for https links to Element domains
                 ) {
-                    return null;
+                    return "";
                 } else {
                     return "_blank";
                 }
@@ -225,7 +225,7 @@ export const options: Opts = {
                 // malformed URI
             }
         }
-        return null;
+        return "";
     },
 };
 
diff --git a/src/modules/ProxiedModuleApi.ts b/src/modules/ProxiedModuleApi.ts
index 1c299133c3..5d93c67eec 100644
--- a/src/modules/ProxiedModuleApi.ts
+++ b/src/modules/ProxiedModuleApi.ts
@@ -211,7 +211,7 @@ export class ProxiedModuleApi implements ModuleApi {
     /**
      * @override
      */
-    public getConfigValue<T>(namespace: string, key: string): T {
+    public getConfigValue<T>(namespace: string, key: string): T | undefined {
         // Force cast to `any` because the namespace won't be known to the SdkConfig types
         const maybeObj = SdkConfig.get(namespace as any);
         if (!maybeObj || !(typeof maybeObj === "object")) return undefined;
diff --git a/src/notifications/PushRuleVectorState.ts b/src/notifications/PushRuleVectorState.ts
index 2ff504815f..2be2228a72 100644
--- a/src/notifications/PushRuleVectorState.ts
+++ b/src/notifications/PushRuleVectorState.ts
@@ -47,7 +47,7 @@ export class PushRuleVectorState {
      *
      * @return [object] list of push-rule actions
      */
-    public static actionsFor(pushRuleVectorState: VectorState): PushRuleAction[] {
+    public static actionsFor(pushRuleVectorState?: VectorState): PushRuleAction[] {
         if (pushRuleVectorState === VectorState.On) {
             return StandardActions.ACTION_NOTIFY;
         } else if (pushRuleVectorState === VectorState.Loud) {
diff --git a/src/utils/FormattingUtils.ts b/src/utils/FormattingUtils.ts
index c72eb594e9..4e9686f997 100644
--- a/src/utils/FormattingUtils.ts
+++ b/src/utils/FormattingUtils.ts
@@ -77,12 +77,11 @@ export function formatCryptoKey(key: string): string {
  */
 export function hashCode(str: string): number {
     let hash = 0;
-    let i;
-    let chr;
+    let chr: number;
     if (str.length === 0) {
         return hash;
     }
-    for (i = 0; i < str.length; i++) {
+    for (let i = 0; i < str.length; i++) {
         chr = str.charCodeAt(i);
         hash = (hash << 5) - hash + chr;
         hash |= 0;
diff --git a/yarn.lock b/yarn.lock
index 9faad3cf29..2578bd33ee 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1595,10 +1595,10 @@
   version "3.2.14"
   resolved "https://gitlab.matrix.org/api/v4/projects/27/packages/npm/@matrix-org/olm/-/@matrix-org/olm-3.2.14.tgz#acd96c00a881d0f462e1f97a56c73742c8dbc984"
 
-"@matrix-org/react-sdk-module-api@^0.0.4":
-  version "0.0.4"
-  resolved "https://registry.yarnpkg.com/@matrix-org/react-sdk-module-api/-/react-sdk-module-api-0.0.4.tgz#da71fc2e4c8143e87b5c2bc067ccbc0c146816fe"
-  integrity sha512-4gcgef3Ne9+Ae0bAErK1Swo9FxTZBDEogX/Iu2kcLWWROOKMjmeWL2PkM83ylsxZ32YY6a6ndRqV/SwRmDeJxg==
+"@matrix-org/react-sdk-module-api@^0.0.5":
+  version "0.0.5"
+  resolved "https://registry.yarnpkg.com/@matrix-org/react-sdk-module-api/-/react-sdk-module-api-0.0.5.tgz#78bd80f42b918394978965ef3e08496e97948c7a"
+  integrity sha512-QhH1T1E6Q6csCUitQzm32SRnX49Ox73TF5BZ4p5TOGFpPD3QuYc5/dDC1Yh3xUljgqOS2C6H24qaskw6olCtfQ==
   dependencies:
     "@babel/runtime" "^7.17.9"