When the DFS IO handler is used, no Image Placeholder will be generated.

Steps to reproduce
1. Clean installation of eZ Platform 2.5 or Ibexa DXP 3.2+ with enabled clustering (DFS + NFS): https://doc.ibexa.co/en/latest/guide/clustering/
3. Set up an Image Placeholder: https://doc.ibexa.co/en/latest/guide/images/#semantic-configuration
2. Create a new Image Content.
3. Delete the image file from NFS that Image Content is using.
4. View the Image Content.

Result
Broken image - no placeholder generated.

Expected result
Image placeholder is generated and displayed normally.