Window.open with 'noopener' opens a new window instead of a new tab

Honestly i think your code is fine but you can try a different implementation:

var yourWindow = window.open();
yourWindow.opener = null;
yourWindow.location = "http://someurl.here";
yourWindow.target = "_blank";

Another approach that will solve this in one line is to access the opener property directly and set it to null to make use of the fact that window.open() returns a Window object. This will work across all browsers to open a new tab with a null window.opener.

window.open(url, '_blank').opener = null;