By setting Gmail as Chrome's default mail handler, all mail links on web pages can be opened in Gmail.

Setting Gmail as the default mail Handler

1. Open Chrome. Search the right side of the address bar for an icon with two overlapping diamond shapes. Click the icon. 

2. Select your Gmail account and press Done.

If you can't see the icon, update your Chrome. If for some reason you aren't still able to see the icon, go to Chrome's Settings > Advanced settings > under Privacy, Content settings... > under Handlers, Manage handlers... > select Gmail from the mailto dropdown > click Done.