Adding/Updating a link to an uploaded image in a Trix field

When you drag an image into a Trix field it creates a link to the image source automatically. If you then select the uploaded image in the Trix editor the link/unlink button is grey and unclickable. So you can not remove or update this link to something else.

Is there a way to enable link editing on uploaded images in Trix? either to remove the existing link or to customise to something else?