A Safari extension that makes mailto:
links use GMail in your browser.
For some reason macOS does not seem to support opening mailto:
in Safari.
You can choose Safari to be your default email application, but nope,
when you click on a mailto:
link you get the error message,
"Safari cannot open the page because the address is invalid."
This extension works around that by translating those clicks into opening a new GMail tab with the email ready to be sent.
To install, download the extension and then run the app. I haven't dealt with code signing (read as: paid for an Apple developer account) so you need to turn on Developer mode in Safari and then allow running of unsigned extensions.
While this is a Safari browser extension I'm pretty sure that it'd work with Chrome, Firefox, or any other browser supporting the WebExtensions API. See the files in gmailto Extension/Resources/
.
Click on mailto:
links and they should open a new compose tab in GMail.
Here's a mailto link to test it out on.
The Send Email icon is by Icons8.