This is rather odd and just started. When I rotate my iPhone 6 (iOS 9.1) to Landscape mode, the Bookmarks are now always showing, which of course takes up half the display negating the reason I rotate to Landscape.
The only thing that I know of that happened coincidentally to this was my bookmarks being wiped out by a web browser issue on my PC forcing me to restore them from a backup on the desktop - I sync my bookmarks from my desktop PC via the iCloud Bookmarks plug in for Firefox.
I can find no settings on the phone to deal with this, and I have rebooted twice, once normal and once as a hard reset, no change.
The only thing that I know of that happened coincidentally to this was my bookmarks being wiped out by a web browser issue on my PC forcing me to restore them from a backup on the desktop - I sync my bookmarks from my desktop PC via the iCloud Bookmarks plug in for Firefox.
I can find no settings on the phone to deal with this, and I have rebooted twice, once normal and once as a hard reset, no change.