diff --git a/app/controllers/notifications/trays_controller.rb b/app/controllers/notifications/trays_controller.rb
index c2bac662ad..fbb24000b8 100644
--- a/app/controllers/notifications/trays_controller.rb
+++ b/app/controllers/notifications/trays_controller.rb
@@ -1,9 +1,27 @@
 class Notifications::TraysController < ApplicationController
+  MAX_ENTRIES_LIMIT = 100
+
   def show
-    @notifications = Current.user.notifications.preloaded.unread.ordered.limit(100)
+    @notifications = unread_notifications
+    if include_unread?
+      @notifications += read_notifications
+    end
 
     # Invalidate on the whole set instead of the unread set since the max updated at in the unread set
     # can stay the same when reading old notifications.
-    fresh_when Current.user.notifications
+    fresh_when etag: [ Current.user.notifications, include_unread? ]
   end
+
+  private
+    def unread_notifications
+      Current.user.notifications.preloaded.unread.ordered.limit(MAX_ENTRIES_LIMIT)
+    end
+
+    def read_notifications
+      Current.user.notifications.preloaded.read.ordered.limit(MAX_ENTRIES_LIMIT)
+    end
+
+    def include_unread?
+      ActiveModel::Type::Boolean.new.cast(params[:include_unread])
+    end
 end
diff --git a/app/views/notifications/_notification.json.jbuilder b/app/views/notifications/_notification.json.jbuilder
index ba27c5425e..5a6e604c7b 100644
--- a/app/views/notifications/_notification.json.jbuilder
+++ b/app/views/notifications/_notification.json.jbuilder
@@ -9,8 +9,10 @@ json.cache! notification do
   json.creator notification.creator, partial: "users/user", as: :user
 
   json.card do
-    json.(notification.card, :id, :title, :status)
+    json.(notification.card, :id, :number, :title, :status)
+    json.board_name notification.card.board.name
     json.url card_url(notification.card)
+    json.column notification.card.column, partial: "columns/column", as: :column if notification.card.column
   end
 
   json.url notification_url(notification)
diff --git a/app/views/notifications/trays/show.json.jbuilder b/app/views/notifications/trays/show.json.jbuilder
new file mode 100644
index 0000000000..0c2928cef7
--- /dev/null
+++ b/app/views/notifications/trays/show.json.jbuilder
@@ -0,0 +1 @@
+json.array! @notifications, partial: "notifications/notification", as: :notification
diff --git a/app/views/users/_user.json.jbuilder b/app/views/users/_user.json.jbuilder
index 0884f225ab..ed05bc67f4 100644
--- a/app/views/users/_user.json.jbuilder
+++ b/app/views/users/_user.json.jbuilder
@@ -5,4 +5,5 @@ json.cache! user do
   json.created_at user.created_at.utc
 
   json.url user_url(user)
+  json.avatar_url user_avatar_url(user)
 end
diff --git a/test/controllers/notifications/trays_controller_test.rb b/test/controllers/notifications/trays_controller_test.rb
index 07034fff0d..57e2997e90 100644
--- a/test/controllers/notifications/trays_controller_test.rb
+++ b/test/controllers/notifications/trays_controller_test.rb
@@ -11,4 +11,24 @@ class Notifications::TraysControllerTest < ActionDispatch::IntegrationTest
     assert_response :success
     assert_select "div", text: /Layout is broken/
   end
+
+  test "show as JSON" do
+    expected_ids = users(:kevin).notifications.unread.ordered.limit(100).pluck(:id)
+
+    get tray_notifications_path(format: :json)
+
+    assert_response :success
+    assert_equal expected_ids, @response.parsed_body.map { |notification| notification["id"] }
+  end
+
+  test "show as JSON with include_unread includes read notifications" do
+    notifications = users(:kevin).notifications
+    expected_ids = notifications.unread.ordered.limit(100).pluck(:id) +
+      notifications.read.ordered.limit(100).pluck(:id)
+
+    get tray_notifications_path(format: :json, include_unread: true)
+
+    assert_response :success
+    assert_equal expected_ids, @response.parsed_body.map { |notification| notification["id"] }
+  end
 end
diff --git a/test/controllers/notifications_controller_test.rb b/test/controllers/notifications_controller_test.rb
index e4e7bec38a..3b2223ae43 100644
--- a/test/controllers/notifications_controller_test.rb
+++ b/test/controllers/notifications_controller_test.rb
@@ -23,5 +23,9 @@ class NotificationsControllerTest < ActionDispatch::IntegrationTest
     assert_not_nil notification["created_at"]
     assert_not_nil notification["card"]
     assert_not_nil notification["creator"]
+    assert_not_nil notification.dig("creator", "avatar_url")
+    assert_not_nil notification.dig("card", "number")
+    assert_not_nil notification.dig("card", "board_name")
+    assert_not_nil notification.dig("card", "column")
   end
 end