scroll bar disappears in photos library

The scroll bar at the right in iCloud Photos library appears for a short time if I resize the window but cannot be activated or used otherwise. This is a significant problem when going to the older sections of my photo library. Trackpad is semi-useful, as you have to keep swiping , and after a while the library gets confused and simply stops. This is a basic feature that no one should have a problem with. Doesn't Apple use a function checklist before releasing an update? The fact that users have to point out a failing of this nature does not reflect well on the execution or monitoring of code mods. And its not the first case of simple things going wrong. Its just plain annoying.