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Steps

Firefox instructions

1. Navigate to Tool - Options or enter about:preferences into the address bar.

2. Scroll down to the Applications section.

3. Search for mailto and click on the arrow over on the right.

4. Select your application of choice.

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ChromeInstructions ChromeInstructions

Chrome instructions

1. Sign into Gmail.

2. On the right side of the address bar, click on the double-diamond shape next to the bookmark star.
   

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1. Image Added

2. Select Allow; Done

If the double-diamond shape is not visible, then follow the instructions at https://support.google.com/a/users/answer/9308783?hl=en

Safari, Internet Explorer, and Microsoft Edge

1. Configuring mailto is not supported by default on these browsers.

2. When opening a mailto link for the first time, they will either open in a separate mail application or prompt you for a selection of application. This includes Outlook, Windows' Mail app, Apple's Mail app, or Google Chrome. 

3. If opening in Google Chrome, it must be set up as described in the Chrome instructions above or the link will open in a blank tab.

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