Flagging Long Subjects

From PluginWiki

Yahoo truncates subjects at 63 characters, so if you have a subject line longer than that, your members won't see all of it when they look at the Messages page (though they may still see it all by email).

You can configure the plugin to flag subjects which are too long. You do this from Even More Advanced Options:

Put the number of characters you want to use as a limit in:

• Remember 63 is Yahoo's limit. The plugin defaults to using this.
  
• 0 means no limit.

You can also choose the colour that gets used (click on the button) and the text it inserts.

You'll see the excess characters in long subject lines flagged like this: