display:none; in link

Today I discovered that a site which is using my live widget has modified the link back with display:none;

It basically hides the backlink for the user. Since I have no direct experience with this css applied on links, I wonder if the backlink is still legit in the eyes of Big G. It's the first time it happened and I've read some conflicting articles on the net. So please, share your thoughts if you have been using this method for linking.

The backlink is most probably still valuable for Google.

Just don't overdo it. It's an old-school tactic that won't pass a manual review.

Link is still visible.

But does not look good.

It is like stuffing links.

As website owner is using your link, you can ask him to provide proper link.

As long as you can find the link in the site's HTML code, yes Google will be able to find out that it's a link pointing to your site.