How to test telephone link?

[frankandrobot]

I have an app with a call button---when you click on the button it follows a link to make a phone call (an anchor with a telephone link.) On mobile, this opens the Phone app. On desktop, this asks you if you want to make a call. (You can see it here on a small mobile screen: https://leandertile.com.)

However, in cypress I am unable to test this link---clicking on the button causes Cypress to fail. Closer inspection reveals that clicking on the link makes Cypress try to load a new page?

[jjhelguero]

Do you know how the app issues the prompt?

This shows you how to test a prompt.
https://glebbahmutov.com/blog/onbeforeunload/#solution-3-prevent-confirmation-prompt