Portal login hangs up on accountswitcher-callback.html

[FredSpataro]

Hi All, 

Got a portal issue that came up recently, not sure what we tweaked that caused the issue but ... 

1. login to the portal using a built-in account
2. web page hangs up on the "vertical bars loading image" on the url: {host}/portal/home/accountswitcher-callback.html?{yada}
3. edit url to the main portal home and portal loads with the account logged in

So it seems like login is successful but something in the javascript running the accountswitcher-callback.html is failing to complete.  No error in the dev tools console.  Network requests all look good. 

Any thoughts on what might be hanging it up? 

Thanks