Hidden Page Parts:

Global Navigation: (yellow/white sidebar on the left)
Right Sidebar: (usually referred to as "Popular Pages")
Wikia Bar: (floating on the bottom right)
Fan Feed: (located at the bottom, containing unrelated content for the current page)
Fandom Pop-up Notifications: (mostly containing marketing material)

Adjusted Width of:

Changes in latest Version 1.4.6:

Tested on Wikia Pages:

Feel free to report bugs using the support email or leave a review. :D