The layout for doc.ezplatform.com needs the following improvements:

Fixes:

• Fix broken scrollspy in right navigation (does not move when scrolling upwards)
• "View on github" link in the latest branch should link to existing branches on github
• In the left navigation the current page should be centered on the screen

Improvements (in order of importance):

• Make main text column wider
• Move the version switcher to top-right corner (see Symfony doc for an example)
• Make note boxes with titles (e.g. "Beginner tutorial" in https://doc.ezplatform.com/en/master/getting_started/first_steps/) act like anchors.
• Ensure wide code blocks are readable by:
  • line breaks?
  • zoomed-out modal?
• Add a dark mode?