Issue
The Chromebook screen doesn’t rotate in tablet mode.
Quick fix
Hit Ctrl > Shift > Refresh, or fix it in Settings.
The full story
One of the nice things about many Chromebooks is that you can fold the keyboard back (or detach it) and use it as a tablet. However, something may occasionally go wrong so that when you try to use it as a tablet and physically rotate it, the screen on your Chromebook won’t make the 90-degree rotation that you need. This can be really irritating — but there are a couple of very easy ways to adjust it.
How to fix it
Your Chromebook’s screen should rotate 90 degrees every time you put it in tablet mode — in other words, when you fold the keyboard back or remove it and hold the device like a tablet. If it’s…
Source: TheVerge