rel="noopener"
The noopener keyword for the rel attribute of the {{HTMLElement("a")}} , {{HTMLElement("area")}} , and {{HTMLElement("form")}} elements instructs the browser to navigate to the target resource without granting the new browsing context access to the document that opened it — by not setting the {{DOMxRef("Window.opener")}} property on the opened window (it returns null).
This is especially useful when opening untrusted links, in order to ensure they cannot tamper with the originating document via the {{DOMxRef("Window.opener")}} property (see About rel=noopener for more details), while still providing the Referer HTTP header (unless noreferrer is used as well).
Note that when noopener is used, nonempty target names other than _top, _self, and _parent are all treated like _blank in terms of deciding whether to open a new window/tab.
[!NOTE] Setting
target="_blank"on<a>,<area>and<form>elements implicitly provides the samerelbehavior as settingrel="noopener"which does not setwindow.opener.
Specifications
{{Specifications}}
Browser compatibility
{{Compat}}