API: Cannot get app_name by window_list function

I’m trying to use TotalSpaces2.window_list api to get all windows.
It works fine except app_name is empty string.

Here’s sample code:

require 'totalspaces2'

windows = TotalSpaces2.window_list
puts windows[0]

# output
{:window_id => 77524,
 :title => "BinaryAge",
 :frame => "{{1064, -1176}, {856, 1174}}",
 :is_on_all_spaces => false,
 :app_name => "",
 :display_id => 1952339654,
 :space_number => 2}

In my environment, app_name is “” for all windows.
Is this a bug?

Thanks in advance.

I see we are using a deprecated api to get that info, I wonder if it has stopped working.
I’ll look further into it.