You can set the amount of characters per subject that can be typed before a warning indicator will be displayed (the background will turn amber).

 

Right-click a subject, a menu will appear, click 'Set warning number of characters'.

 

In the text box, type in the approximate number of characters before the warning indicator will appear.

 

Note: Enter zero ( '0' ) to turn off the warning indicator for this subject.

 

If this is the first time you have setup a warning amount you will be asked if you wish to turn on the character limit system.  Click 'Yes'.

 

For more information about character limits, see the text length limits section.