If you apply the fix from EZP-24350 and try to delete an ezflow block, you will see that block changes position with other existing block and is not removed.

Steps to Reproduce

1. Create a landing page
2. In the layout attribute, at three eZ Flow blocks.
3. Try to delete the one in the middle, and confirm it will change places with one of the others

^{Notes: In my tests with Firefox I didn't get any javascript error, but got a popup with the information in the attached popup.js file}