It is not possible to upload an image directly to a TB entry in order to have a visual reference of the term from the Editor.
It is possible to add URLs leading to images to the URL field in the TB entry, however, this requires users to open external pages.
Add an image field to the in order to allow the upload of pictures to TB entries. The uploaded picture could be displayed at the bottom of the CAT pane whenever the TB match is selected.
In cases of confidential content, using URLs is not possible for security reasons, as those could be easily shared with unauthorized external users. Having a visual reference inside the Editor would improve and speed linguists' performance, and also overcome the mentioned security issues.