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On Mac OS X, clicking on the phone icons may bring up a Facetime message. Since you normally cannot make a phone call from your desktop or laptop computer, Facetime will allow you to make the call via WiFi on your iPhone. At the minimum, you will see the number so you can call it as you normally would, so do allow Facetime to do it's job.
For the Windows Edge browser, clicking the phone icon may result in displaying the number, or bringing up a Skype message, which you can use. With Internet Explorer you may have to right click on the phone number and select Properties to actually see the number.