It is usually quite easy to spot mailto: links, and hovering over the link will usually make it extra clear (at least in Chrome, in the bottom left corner a sma

It is usually quite easy to spot mailto: links, and hovering over the link will usually make it extra clear (at least in Chrome, in the bottom left corner a small box with the url's location is displayed). I usually just right-click the link and select "Copy email address" (chrome) and paste it into gmail.