diff --git a/Gemfile.lock b/Gemfile.lock
index 41fc86c8af..1f8645a59e 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -702,7 +702,7 @@ GEM
     rqrcode_core (1.2.0)
     rspec-core (3.13.0)
       rspec-support (~> 3.13.0)
-    rspec-expectations (3.13.0)
+    rspec-expectations (3.13.1)
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.13.0)
     rspec-github (2.4.0)
@@ -710,7 +710,7 @@ GEM
     rspec-mocks (3.13.1)
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.13.0)
-    rspec-rails (6.1.2)
+    rspec-rails (6.1.3)
       actionpack (>= 6.1)
       activesupport (>= 6.1)
       railties (>= 6.1)
@@ -891,7 +891,7 @@ GEM
     xorcist (1.1.3)
     xpath (3.2.0)
       nokogiri (~> 1.8)
-    zeitwerk (2.6.15)
+    zeitwerk (2.6.16)
 
 PLATFORMS
   ruby
diff --git a/app/javascript/mastodon/locales/ko.json b/app/javascript/mastodon/locales/ko.json
index aa05887d65..c4c084d98e 100644
--- a/app/javascript/mastodon/locales/ko.json
+++ b/app/javascript/mastodon/locales/ko.json
@@ -32,7 +32,7 @@
   "account.featured_tags.last_status_never": "게시물 없음",
   "account.featured_tags.title": "{name} 님의 추천 해시태그",
   "account.follow": "팔로우",
-  "account.follow_back": "맞팔로우",
+  "account.follow_back": "맞팔로우 하기",
   "account.followers": "팔로워",
   "account.followers.empty": "아직 아무도 이 사용자를 팔로우하고 있지 않습니다.",
   "account.followers_counter": "{counter} 팔로워",
@@ -53,7 +53,7 @@
   "account.mute_notifications_short": "알림 뮤트",
   "account.mute_short": "뮤트",
   "account.muted": "뮤트됨",
-  "account.mutual": "상호 팔로우",
+  "account.mutual": "맞팔로우 중",
   "account.no_bio": "제공된 설명이 없습니다.",
   "account.open_original_page": "원본 페이지 열기",
   "account.posts": "게시물",
diff --git a/app/javascript/mastodon/store/typed_functions.ts b/app/javascript/mastodon/store/typed_functions.ts
index dae37e6225..e5820149db 100644
--- a/app/javascript/mastodon/store/typed_functions.ts
+++ b/app/javascript/mastodon/store/typed_functions.ts
@@ -82,13 +82,19 @@ export function createThunk<Arg = void, Returned = void>(
 const discardLoadDataInPayload = Symbol('discardLoadDataInPayload');
 type DiscardLoadData = typeof discardLoadDataInPayload;
 
-type OnData<LoadDataResult, ReturnedData> = (
+type OnData<ActionArg, LoadDataResult, ReturnedData> = (
   data: LoadDataResult,
   api: AppThunkApi & {
+    actionArg: ActionArg;
     discardLoadData: DiscardLoadData;
   },
 ) => ReturnedData | DiscardLoadData | Promise<ReturnedData | DiscardLoadData>;
 
+type LoadData<Args, LoadDataResult> = (
+  args: Args,
+  api: AppThunkApi,
+) => Promise<LoadDataResult>;
+
 type ArgsType = Record<string, unknown> | undefined;
 
 // Overload when there is no `onData` method, the payload is the `onData` result
@@ -101,18 +107,18 @@ export function createDataLoadingThunk<LoadDataResult, Args extends ArgsType>(
 // Overload when the `onData` method returns discardLoadDataInPayload, then the payload is empty
 export function createDataLoadingThunk<LoadDataResult, Args extends ArgsType>(
   name: string,
-  loadData: (args: Args) => Promise<LoadDataResult>,
+  loadData: LoadData<Args, LoadDataResult>,
   onDataOrThunkOptions?:
     | AppThunkOptions
-    | OnData<LoadDataResult, DiscardLoadData>,
+    | OnData<Args, LoadDataResult, DiscardLoadData>,
   thunkOptions?: AppThunkOptions,
 ): ReturnType<typeof createThunk<Args, void>>;
 
 // Overload when the `onData` method returns nothing, then the mayload is the `onData` result
 export function createDataLoadingThunk<LoadDataResult, Args extends ArgsType>(
   name: string,
-  loadData: (args: Args) => Promise<LoadDataResult>,
-  onDataOrThunkOptions?: AppThunkOptions | OnData<LoadDataResult, void>,
+  loadData: LoadData<Args, LoadDataResult>,
+  onDataOrThunkOptions?: AppThunkOptions | OnData<Args, LoadDataResult, void>,
   thunkOptions?: AppThunkOptions,
 ): ReturnType<typeof createThunk<Args, LoadDataResult>>;
 
@@ -123,8 +129,10 @@ export function createDataLoadingThunk<
   Returned,
 >(
   name: string,
-  loadData: (args: Args) => Promise<LoadDataResult>,
-  onDataOrThunkOptions?: AppThunkOptions | OnData<LoadDataResult, Returned>,
+  loadData: LoadData<Args, LoadDataResult>,
+  onDataOrThunkOptions?:
+    | AppThunkOptions
+    | OnData<Args, LoadDataResult, Returned>,
   thunkOptions?: AppThunkOptions,
 ): ReturnType<typeof createThunk<Args, Returned>>;
 
@@ -159,11 +167,13 @@ export function createDataLoadingThunk<
   Returned,
 >(
   name: string,
-  loadData: (args: Args) => Promise<LoadDataResult>,
-  onDataOrThunkOptions?: AppThunkOptions | OnData<LoadDataResult, Returned>,
+  loadData: LoadData<Args, LoadDataResult>,
+  onDataOrThunkOptions?:
+    | AppThunkOptions
+    | OnData<Args, LoadDataResult, Returned>,
   maybeThunkOptions?: AppThunkOptions,
 ) {
-  let onData: OnData<LoadDataResult, Returned> | undefined;
+  let onData: OnData<Args, LoadDataResult, Returned> | undefined;
   let thunkOptions: AppThunkOptions | undefined;
 
   if (typeof onDataOrThunkOptions === 'function') onData = onDataOrThunkOptions;
@@ -177,7 +187,10 @@ export function createDataLoadingThunk<
   return createThunk<Args, Returned>(
     name,
     async (arg, { getState, dispatch }) => {
-      const data = await loadData(arg);
+      const data = await loadData(arg, {
+        dispatch,
+        getState,
+      });
 
       if (!onData) return data as Returned;
 
@@ -185,6 +198,7 @@ export function createDataLoadingThunk<
         dispatch,
         getState,
         discardLoadData: discardLoadDataInPayload,
+        actionArg: arg,
       });
 
       // if there is no return in `onData`, we return the `onData` result
diff --git a/app/serializers/rest/notification_serializer.rb b/app/serializers/rest/notification_serializer.rb
index 417245d19d..966819585f 100644
--- a/app/serializers/rest/notification_serializer.rb
+++ b/app/serializers/rest/notification_serializer.rb
@@ -1,7 +1,7 @@
 # frozen_string_literal: true
 
 class REST::NotificationSerializer < ActiveModel::Serializer
-  attributes :id, :type, :created_at
+  attributes :id, :type, :created_at, :group_key
 
   belongs_to :from_account, key: :account, serializer: REST::AccountSerializer
   belongs_to :target_status, key: :status, if: :status_type?, serializer: REST::StatusSerializer
@@ -13,6 +13,10 @@ class REST::NotificationSerializer < ActiveModel::Serializer
     object.id.to_s
   end
 
+  def group_key
+    object.group_key || "ungrouped-#{object.id}"
+  end
+
   def status_type?
     [:favourite, :reblog, :status, :mention, :poll, :update].include?(object.type)
   end