(Full disclosure, it took a little more than right-clicking to download that image. OpenSea apparently purposefully makes it hard to download images. Not terribly hard, though. Only took me a couple of minutes to figure out.)
For me it's win+shift+s on windows, not ctrl. At least if you're taking about being able to select part of your screen to screenshot, without having to crop after the fact.
Also alt+printscreen to screenshot just the selected window.