diff --git a/src/RoomNotifs.ts b/src/RoomNotifs.ts
index c484d68f18..c1f94cd71c 100644
--- a/src/RoomNotifs.ts
+++ b/src/RoomNotifs.ts
@@ -219,7 +219,10 @@ function isRuleRoomMuteRuleForRoomId(roomId: string, rule: IPushRule): boolean {
 }
 
 function isMuteRule(rule: IPushRule): boolean {
-    return rule.actions.length === 1 && rule.actions[0] === PushRuleActionName.DontNotify;
+    // DontNotify is equivalent to the empty actions array
+    return (
+        rule.actions.length === 0 || (rule.actions.length === 1 && rule.actions[0] === PushRuleActionName.DontNotify)
+    );
 }
 
 export function determineUnreadState(
diff --git a/test/RoomNotifs-test.ts b/test/RoomNotifs-test.ts
index e80e943e3c..505de622bc 100644
--- a/test/RoomNotifs-test.ts
+++ b/test/RoomNotifs-test.ts
@@ -64,6 +64,13 @@ describe("RoomNotifs test", () => {
         expect(getRoomNotifsState(client, room.roomId)).toBe(RoomNotifState.Mute);
     });
 
+    it("getRoomNotifsState handles mute state for legacy DontNotify action", () => {
+        const room = mkRoom(client, "!roomId:server");
+        muteRoom(room);
+        client.pushRules!.global.override![0]!.actions = [PushRuleActionName.DontNotify];
+        expect(getRoomNotifsState(client, room.roomId)).toBe(RoomNotifState.Mute);
+    });
+
     it("getRoomNotifsState handles mentions only", () => {
         (client as any).getRoomPushRule = () => ({
             rule_id: "!roomId:server",
diff --git a/test/test-utils/test-utils.ts b/test/test-utils/test-utils.ts
index 1e2fe78ca1..b4de68df35 100644
--- a/test/test-utils/test-utils.ts
+++ b/test/test-utils/test-utils.ts
@@ -34,7 +34,6 @@ import {
     RoomType,
     KNOWN_SAFE_ROOM_VERSION,
     ConditionKind,
-    PushRuleActionName,
     IPushRules,
     RelationType,
 } from "matrix-js-sdk/src/matrix";
@@ -796,7 +795,7 @@ export function muteRoom(room: Room): void {
                     pattern: room.roomId,
                 },
             ],
-            actions: [PushRuleActionName.DontNotify],
+            actions: [],
         },
     ];
 }