Normally, the comments attached to the elements are not visible in the diagram, unless you open the editor for an element or activate mode "Comments plus text".

Mode "Show comments?" makes comments visible on demand only and therefore induces two effects:

• Commented elements are marked with a vertical gray bar along the left edge.
• While the cursor hovers over a commented element (indicator see above), the comment will pop up as tooltip. (Note: Very abundant comments may induce a rapidly intermittent popup behaviour while the cursor is hovering over the respective element.)

To enable / disable the comment mode use the menu item "Show comments?" in the menu "View" (before version 3.32-13: menu "Diagram"):

Completely different ways to show comments are offered by modes "Switch text/comments?" and "Comments plus texts?".

Note that mode "Switch text/comments?" inverts the mechanism of both the gray marker bars and the tooltips: The gray bars will then indicate elements with non-empty text fields, and the tooltips will show the text instead of the comment (which is then drawn in the diagram).