old_contents: def features_nav():
      return [
          {
              "name": "Features",
              "link": "main.features",
          },
          {
              "name": "Roadmap",
              "link": "main.roadmap",
          },
          {
              "name": "Security",
              "link": "main.security",
          },
          {
              "name": "Performance",
              "link": "https://www.gov.uk/performance/govuk-notify",
              "external_link": True,
          },
          {
              "name": "Terms of use",
              "link": "main.terms",
          },
          {
              "name": "Using Notify",
              "link": "main.using_notify",
          },
      ]
  
new_contents: def features_nav():
      return [
          {
              "name": "Features",
              "link": "main.features",
          },
          {
              "name": "Roadmap",
              "link": "main.roadmap",
          },
          {
              "name": "Security",
              "link": "main.security",
          },
          {
              "name": "Terms of use",
              "link": "main.terms",
          },
          {
              "name": "Using Notify",
              "link": "main.using_notify",
          },
      ]
  
subject: Remove performance link from features nav