When I go to a page history, click on Contributions by User, type my name, and get the list, clicking on the diff takes me to a page with http://www.homeimprovement.com prefixed to it.
http://https//en.wikipedia.org/w/index.php?title=Mumbai&diff=prev&oldid=670092564 goes to http://www.homeimprovement.com/en.wikipedia.org/w/?title=Mumbai&diff=prev&oldid=670092564
This happens with Firefox.
The issue is because the urls on the page point to https and not https:
A missing : is resulting in this error.