Your exhibition thumbnail is the small preview image. This thumbnail will be used on your Discover profile if you decide to set your exhibition as a feature exhibit, and will also be displayed when loading and before entering the exhibition.
Once it is curated, if no image is previously provided as thumbnail in Step 2, the system randomly selects an artwork from the exhibit every time it generates a thumbnail. Note that the system will only select from those non png files on the exhibit.
You can select the thumbnail for the loader by uploading the jpeg you want to use in the Step 2. This can be done by going to your Virtual Exhibitions, selecting the exhibition and pressing "edit". Once on the settings, head to the second section, "Venue."
At the top left, you will find there’s an empty gallery image with a button that says “Replace Image”. Click or tap the button and upload your own thumbnail image for the exhibition.
When searching for the exhibition on Discover, you will notice the thumbnail might differ, this is because the thumbnail is set by the first no PNG image on the exhibit.
Bear in mind the loader will only display JPEG images, otherwise you might see a "broken image" icon on display.