title: How to center an overflowing sidescroll when not overflowing using ..flexbox?
body: <p>So I've got this sidescroll constrained by height (say, 50vh). This works fine</p>
  <p><a href="https://i.stack.imgur.com/3egUw.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/3egUw.png" alt="Sidescroll" /></a></p>
  <p>Now comes the hard part, when the content is less wide than the browser I would like the images to be centered! Is this possible?</p>
  <p><a href="https://i.stack.imgur.com/LMxIE.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/LMxIE.png" alt="Centered" /></a></p>
  <p>If I use justify-content:center I get this weird behaviour where a part of the first image is outside the viewport - and I don't know why that happens, but it happens in both FF and Brave, so at least it's consistent.</p>
  <p>This only happens when the content is wider than the browser. If the content is less wide than the browser it actually centers it fine, but the overflowing mechanism is a bit ..wierd?</p>
  <p><a href="https://i.stack.imgur.com/9Ed3K.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/9Ed3K.png" alt="enter image description here" /></a></p>