Images you upload through a module's image field (Background Image, Featured Image, gallery photos, etc.) go into Sprwt's own file storage and are inserted with an absolute URL, so they keep working if you move or clone the module. JPG, PNG and WebP are accepted, and there is an automatic size limit: uploads processed as JPG or PNG are resized to fit a default maximum of 1920×1080 px (kept proportional) and JPG uploads have their quality reduced to 70% — a file in a different format (e.g. a PNG selected into a JPG-typed field) is also converted to the target format. So you don't need to manually shrink a hero image before uploading, though a very large original will still take longer to upload. Blog featured images are recommended at 1200×630 px (JPG, PNG or WebP).