Regression: Mobile Style
vBulletin 4 has a mobile style and VaultWiki 3 made very extensive use of it. However, VaultWiki 4 doesn't work under it at all. At the very least under Android Browser, users are presented with a completely blank page when trying to access the wiki.
This is particularly problematic for VaultWiki.org, because 15% of our traffic comes from Android Browser, and almost all of it bounces, likely a direct result of this issue.