UserScript to hide room wasting/attention diverting sidebars/banners on ALL StackOverflow and StackExchange sites & maximise content area
direct stable URL to newest version (autoupdating):
if you use TamperMonkey or other good UserScript extension with your Firefox or Chromium-based browser, it should offer the option to install that UserScript when you open the URL, otherwise add it in TamperMonkey → Utilities → Install from URL