Gallery extension does not show in list

I am trying to install the VRT Network Equipment gallery extension and I do not see the VRT folders in the gallery list.

Steps to reproduce:

  1. Default install of Ubuntu 16.04 with LibreOffice Draw 5.1.6.2
  2. Download the VRT Network Equipment 1.2.0 extension from https://extensions.libreoffice.org/extensions/vrt-network-equipment
  3. In LibreOffice Draw navigate to Tools > Extension Manager
  4. Click the Add button
  5. Select the vrtnetworkequipment_1-2-0-lo.oxt file
  6. Click Open
  7. Navigate to View > Clip Art Gallery
  8. Look in the Gallery list to see if VRT folders are there

I have tried restarting LibreOffice and ubuntu. I have tried disabling and re-enabling the extension. I have tried re-downloading, removing, and adding the extension again.