Checkboxes not visible on admin forms using default Shiny theme.

[timcoxopc]

On a fresh install of 7.x-2.20 if you add a checkbox field to a content type there is no visible option under 'Default value'. If you then try to create a node with this content type the checkbox field will not be a visible option on the form (although the help text will be visible). In both cases the checkbox exists but has an opacity of 0 set by line 157 of shiny.css. There is a patch available for the Shiny theme discussed here: https://www.drupal.org/project/shiny/issues/2647644 that addresses this issue.