In the selected email: When you hover over the email address link, what do you see in the bottom status bar? eg: mailto:followed by email address which is exactly the same as the email address link in email or different ?

I'm not sure, what effect would that have ? I do know that when I hover over the link and right click "copy email address", that works without a problem

Well that is the standard test that used to determine whether any link is actually linking to the 'visual' link you see or whether it is bogus. It is the first thing I do to check that it will do what it appears to do. Basic security practise.

It would also tell me if the link uses the correct mailto call.

So please check and report back.