Issue Description

The embedded code editor has strange cursor positioning behaviour. If the cursor is on a line and I hit the End key, sometimes the cursor will move to some point in the middle of a line and sometimes it won't move at all. If I click at a point in the editor that is past the end of a line, sometimes the cursor will move there while other times it won't move to a point even if it's in the middle of a piece of text.

It seems that my cursor positioning ability is based on the line that is immediately below the current line.

Browser Information

• Browser Name, Version: Chrome 54.0.2840.87
• Operating System: Windows 7 64-bit
• Mobile, Desktop, or Tablet: Desktop