natural height and width of image

[Simbaclaws]

Is it possible to set the height and width of the image to its natural height and width?
Apparently I HAVE to give an attribute to height and width in order to display the image.

I don't know which sizes the images will eventually be because we have a backend that uploads random images. I would like to be able to use the original size of the image rather than setting a size for all the images.

[Simbaclaws]

I can set object-fit:contain on .pswp__img in order to show the correct size.