Static pages were previously missing a margin on the bottom of the
post-title h1. By adding <header> with a post-header class around the
h1, we gain the exact same bottom margin as seen on post (non-static)
pages.
The home and subscribe buttons had backgrounds on static pages, but not
post pages. The backgrounds are now removed from these buttons on
static pages.
Related to TryGhost/Ghost#3599 and TryGhost/Ghost#3389
- The title helper no longer needs triple-stashes to be safe
- The #author can now be used as a context block again
