Steps to reproduce

1. Log in to back office.
2. Go to Content / Content structure.
3. Start creating an Article content.
4. In rich text field attach image file.
5. Being on image picker upload an image file to some folder.
6. Click on 'X' button at the top.

Actual result:

An exception occurs

Cannot read properties of null (reading 'split') 

Expected result:

No exception occurs.