A mime type t is a two-part identifier for file formats and format contents used by internet protocols such as HTTP and document file formats such as HTML. As with the file type, there are two ways to specify values for the mime type. On the one hand, the type can be entered in the value field in the attributes. Separate multiple types by comma.
Example: Word and JPEG files are allowed
Image Modified
Alternatively you can click icon Image Modified in the attributes panel to open a separate window, where you can enter one mime type per row. Button Add will add a new row, while the X icon deletes the row. Confirm your changes with Save and discard pressing Cancel.