Which image file types can I upload to an item?
đź”´ StageStock
You can add JPG, JPEG, PNG, GIF, TIF and TIFF images to an item. Each photo can be up to 8 MB.
A file of another type, or a photo over 8 MB, isn't uploaded: the photo window lists it with "this file type is not supported" or "filesize is too large".
To attach a PDF, a spreadsheet or any other file that isn't a photo, use Add/Edit Files on the item instead. How to add photos: Add photos to an item.