In D2778#51900, @mart wrote:

patch in general makes sense

but are you sure svg doesn't export a soucesize? (svgs do have a size in pixels in their root layer and qtsvg supports it)

Of course it does, but it's a size, here we're not interested in giving it a size, we just should make sure it fits the banner.
We could set a 5000x3000 size, but then we'd be rendering it too big then scaling it down.

If you ask me, we should just make Kirigami enforce the look of the banner (despite the developer adding a strictly vertical image), then this property wouldn't be required.

what's the status of that?