Today I Learned

A Hashrocket project

Preventing access to `Window.opener`

When you open a link in a new tab with target="_blank" like so:

<a target="_blank" href="http://some.link">Somewhere</a>

Then the page that you open has access to the original page through Window.opener. Depending on your case you may not want this. Actually I can’t think of a case where you do want the new tab to refer back to the opening tab.

To prevent Window.opener access use rel="noopener":

<a target="_blank" href="http://some.link" rel="noopener">Somelink</a>

At this moment, this is not available in IE or Edge, check out the caniuse site.

H/T Dillon Hafer