Hi there,
Still, no luck. Activity filter is still different from your site and to my end, or from the demo even by adding the changes. Have you done some customization before? Though, enqueue is now taking effect.
Would you mind updating your theme to 4.6.4? And make sure the first one is deleted first to make sure that there are no file residues.
Activity filter should trigger ajax request if viewed on network log,s but it isn’t.
Thank and let me know.