From VFXPedia

Comments Tab

The Comments Tab (F9) provides a rich text edit box that can be used to store comments and notes about the composition.

This can be useful for maintaining a todo list for personal purposes or for collaboration between several artists working on the same composition.

Right-clicking in the text box will display a context menu with options for cutting/copying/pasting text to/from the clipboard. Alternately, use the Windows standard keyboard shortcuts Ctrl-X, Ctrl-C and Ctrl-V.