By default, attachments do not have a version query parameter, like, for example JavaScript files have. This plugins adds version numbers to the query strings of attachments.
Version numbers in query strings are useful for caching. If an attachment changes, its version number and, therefore, its URL changes. This allows for the attachment to be cached for an extended period of time or indefintely, for example, with the directive “immutable” of the Cache-Control header.

Attachment URL Version

Adds the version number of attachments to their URL.

Mario Peshev

DevriX

DX Delete Attached Media

Does exactly what its supposed to do. Been looking for a plugin like this for some time.

Great plugin

Automatically deletes attached media from posts and custom post types added via the Media button.

Attachment URL Version vs DX Delete Attached Media