jconsole includes a clickable link to the jconsole documentation in the "About" dialog. This link can easily become invalid when docs are re-organized. See JDK-8263203. It would be best if instead of a URL, the name of the document was referenced, and then the user did a web search for the document instead.

This link is also used by the "Help -> Online User Guide" menu item. This menu item should simply be removed. That would leave "Help -> About" as the only menu item in the Help menu, and when selected, as suggested above, the user will see the name of the document to look up.