With a fresh install of Cubase Pro 9.5.0, the folder icons are missing in the Plug-in Manager:
Confirmed. Looks ugly. See English manual. Same picture there. Must be a feature then. 
But mark and scroll down. It’s buggy. I did no multi select!
See Plugin_Manager_scroll_up_V9_5.jpg.
Here for comparison V9.0.30 which is fine: Plugin_Manager_scroll_up_V9_0.jpg
…and here too:
The plugin hierarchy is obviously missing the icons, since visually there is space for them. I personally don’t care if literal folder icons are used, but some graphic needs to be there to help with visual orientation.
Anyone from Steinberg available to comment?
Issue persists in 9.5.30.
Confirmed: issue still exists in 9.5.30.
It was assigned a few days ago: CAN-16815
Still not fixed in Cubase 9.5.40 and Nuendo 8.3.