Many proprietary file formats used in digital pathology contain not one but two images:

• A high-resolution representation of the tissue on the slide
• A lower-resolution image of the label pasted on the slide. The label can contain a printed barcode for ease of slide identification.

The label control can be collapsed and expanded, as needed. You can also rotate it and convert it to a separate browser tab, but using the buttons underneath

Via Pathomation's tile server you can check if there is a barcode present on the slide label, and attempt to decode it.