That line is called as Print Margin, include
editor.setShowPrintMargin(false);
in your code.
Question
While using ACE editor I've observed that a mysterious line is being displayed at the center of the editor. How do i fix this?
Solution
That line is called as Print Margin, include
editor.setShowPrintMargin(false);
in your code.
OTHER TIPS
It is not a mysterious line but a print margin - simple line at the specified column, to help seeing when lines become too long.
To disable it we can also use,
editor.setOption("showPrintMargin", false)