Just to add to the long list of what us web developers have got to check for is Skype installations.
I've been noticing recently how if you've got Skype installed on your computer, then it is very helpful and turns phone numbers into clickable links for you on websites you visit.
That's great, but the styling it applies adds to the length of the links slightly and can break the layout of websites.
I noticed it this morning on a website that applied to be featured on a wedding planning site we run:
Before skype shortcuts load, everything is fine:
Once Skype loads it's shortcuts, the extra styling means the menu is pushed down to make it almost unreadable: