Expected Behavior

I can delete the image as normal.

Actual Behavior

No ajax call,

Steps to Reproduce the Problem

1. Click on an Image
2. Click delete icon (trash)

Specifications

I checked with the commit: 423f1ad (In my production server) and everything is working fine. But when I use dev-master, or 2.9.0 then it did not work.
Please note that other buttons are working fine, except delete button.