I can't seem to find definitive information on this.
Am I right in thinking that when an image is uploaded to Editor X, it creates different versions of the image in different resolutions and uses them appropriately?
If so, it means it's just a case of uploading the highest resolution image available and let EX do it's thing. Or am I wrong or have maybe missed something? Or perhaps there is still an advisable image size to use as a starting point. TIA