Depending on the presence and amount of content in a note, the outline view will show a slightly different icon in Outline view.
- No note text - a simple half-height rectangle.
- Zero to 7 characters - a vertical rectangle with no horizontal bar inside.
- More than 7 characters - a vertical rectangle with a single horizontal bar inside.
- More than about 60 characters - a vertical rectangle with two horizontal bars inside.
- More than about 500 characters - a vertical rectangle with three horizontal bars inside.
- More than about 4080 characters of text - a vertical rectangle with four horizontal bars inside.
In other views, the presence of note content is shown by a 'dog-ear' icon on the note.
Agent icons are similar except the thick bar is at the bottom, not the top. Disabled ('frozen') agents have an empty bar at the bottom of the icon.
The varying agent/note icon isn't immediately obvious to the eye in Outline view, but once you realise it is there the difference it becomes more intuitive as a way to tell apart Notes and Agents.
Prototype notes also show a light green coloured circle behind the icon (here darkened slightly from default value for better contrast). The colour used is set in the Map Preferences.