After updateat iOS 11.1.2 pe iPad, I noticed that Dock disappears from Home Screen, can be made visible with a swipe (Drag) from up to down, turned on at the bottom of the screen. I mean the same move I normally did to make the Dock Bar visible in an open app on iPad.
Initially I thought it was a feature of the new iOS and that this "auto hide" can be disabled from Settings. Surprise! In "General" → "Multitasking & Dock" there is no option to prevent automatic hiding a Dock in Home Screen.
From what I found out, this is not a feature of iOS 11, but a bug that appeared after the most recent one update of iOS. “Disable auto hide iPad's Dock in Home Screen".
Resolve the automatic disappearance of the Dock from Home Screen, can be solved very easily with a total closure of iPad and reopening. Hold down the button " / Sleep"Then"slide to power off“. After rebooting, Dock will appear in Home Screen and will be withdrawn only when you are in an application.
In our case, the problem arose on a iPad Mini 4 iOS 11.1.2.Disable Auto Hide iPad's Dock in Home Screen - iOS 11