Navigate mode. (a) In this mode, Caryoscope shows a tooltip (small informational pop-up window) whenever the user moves the mouse over a feature. When the user clicks on the feature, Caryoscope navigates to a URL related to the feature. Both the tooltip text and the URL are generated dynamically from the annotations on the feature under the mouse pointer, via the Feature tooltip expression and Feature URL expression settings. (b) Illustration of how the tooltips and URLs are computed from the Feature tooltip expression and Feature URL expression settings and the annotations in the input file.