Navigation panel partially hidden when viewport width is narrow

[raissanorth]

Within the blog section of the CMS, when opening up the Comments tab the Contents | Settings | History tabs at the top right of are partially hidden once the viewport is less than 1170px wide.

Viewport width 1170px and above:

Viewport width less than 1170px

Note that this issue applies only to the Comments tab, but not to any of the other tabs such as Main Content or Categorisation.