Keep same-second unread events and bound idle push connections

test/channels/presence_channel_test.rb

@@ -44,7 +44,7 @@ class PresenceChannelTest < ActionCable::Channel::TestCase
     membership = users(:david).memberships.first
 
     freeze_time do
-      assert_broadcast_on "user_#{users(:david).id}_reads", { room_id: membership.room_id, at: Time.current.to_fs(:epoch) } do
+      assert_broadcast_on "user_#{users(:david).id}_reads", { room_id: membership.room_id, at: Time.current.to_f } do
         subscribe room_id: membership.room_id
       end
     end

test/channels/unread_rooms_channel_test.rb

@@ -35,7 +35,7 @@ class UnreadRoomsChannelTest < ActionCable::Channel::TestCase
       end
     end
 
-    assert_equal [ { "roomId" => direct.id, "at" => message.created_at.to_fs(:epoch) } ], broadcasts
+    assert_equal [ { "roomId" => direct.id, "at" => message.created_at.to_f } ], broadcasts
   end
 
   private