WorldWideWeb could display images, but originally only in a separate window when you clicked on them, similar to the way audio, PDFs, and other multimedia worked (and sometimes still work). The wording of one of the people involved seems to confirm this:

> How was I to know that I was passing an historical milestone, as the one above was the first picture of a band ever to be clicked on in a web browser!"

Source: https://musiclub.web.cern.ch/bands/cernettes/firstband.html