diff --git a/plugins/chat/lib/chat/notifier.rb b/plugins/chat/lib/chat/notifier.rb
index db1a95b36a5..aead57b628b 100644
--- a/plugins/chat/lib/chat/notifier.rb
+++ b/plugins/chat/lib/chat/notifier.rb
@@ -95,7 +95,7 @@ module Chat
       notify_creator_of_inaccessible_mentions(to_notify)
       notify_mentioned_users(to_notify, already_notified_user_ids: already_notified_user_ids)
 
-      to_notify
+      to_notify.except(:all_mentioned_user_ids)
     end
 
     private
diff --git a/plugins/chat/spec/lib/chat/notifier_spec.rb b/plugins/chat/spec/lib/chat/notifier_spec.rb
index f9ff6d7e1a2..9c55e86bf3a 100644
--- a/plugins/chat/spec/lib/chat/notifier_spec.rb
+++ b/plugins/chat/spec/lib/chat/notifier_spec.rb
@@ -121,6 +121,23 @@ describe Chat::Notifier do
       include_examples "channel-wide mentions"
       include_examples "ensure only channel members are notified"
 
+      describe "editing a direct mention into a global mention" do
+        let(:mention) { "hello @#{user_2.username}!" }
+
+        it "doesn't return :all_mentioned_user_ids" do
+          msg = build_cooked_msg(mention, user_1)
+
+          Chat::MessageUpdater.update(
+            guardian: user_1.guardian,
+            chat_message: msg,
+            new_content: "hello @all",
+          )
+
+          to_notify = described_class.new(msg, msg.created_at).notify_edit
+          expect(to_notify[:all_mentioned_user_ids]).not_to be_present
+        end
+      end
+
       describe "users ignoring or muting the user creating the message" do
         it "does not send notifications to the user who is muting the acting user" do
           Fabricate(:muted_user, user: user_2, muted_user: user_1)