Group Album's Navigation

Hi, guys.

Here I'm again with some problem, tested on my site AND  on una.io as well.

1. Just look up in UI/UX Group here (it's open) and find Test Album with Windows sample pictures.

2. Try to enter the album and to open one of pics

3. After picture's opening notice that NAVIGATION BUTTONS (next/previouse) shown in gray-colored, disable manner.  Why? it works well in Album, posted by user. BUT in album, posted IN GROUP - it's desabled.

 I'm talking about THIS VERY site, not my, not yours. THIS means - global bug.

Thanx in advance.