I'd like to use Custom URL to populate embedded schema field. First level and Second level embedded schemas made as repeatable. 
First Level : **NameValueSet**
Second Level : **NameValuePair**.
I am able to pass value to the first child(namevalue) but not for the  further childs within the same embedded schema.Whenever I try to add values to the next childs the popup is opening in new tab instead of in a new popup and `window.dialogArguments` is returning NULL.
If I am repeating the first embedded schema I am able to pass the value to component.
PFB the source of the component:

        <contentschema xmlns="uuid:4cd36b65">
    	<NameValueSet>
    		<NameValuePair>
    			<namevalue>Authenticated - Yes</namevalue>
    		</NameValuePair>
                    <NameValuePair>
    			<namevalue>**UNABLE TO ADD HERE**</namevalue>
    		</NameValuePair>
    	</NameValueSet>
    	<NameValueSet>
    		<NameValuePair>
    			<namevalue>Subproduct - GP</namevalue>
    		</NameValuePair>
    	</NameValueSet>
    	<NameValueSet>
    		<NameValuePair>
    			<namevalue>Subproduct - MRKT</namevalue>
    		</NameValuePair>
    	</NameValueSet>	
    </contentschema>


Please find below how my schema look like:

![enter image description here][1]


  [1]: https://i.sstatic.net/FYKki.jpg