I'm working on a little open source project to overwrite the classic behaviour of mailto links. It's called mailgo (
https://mailgo.js.org). Instead the classic mailto, the idea is to show a modal to give more possibilities to the user, for example to copy the email address. It's WIP (I accept any suggestion!) on the website there is a working demo. If you like it, star the repo on GitHub!
https://github.com/manzinello/mailgo