failed to login when hosting under nginx with a diffrent root path

[ngvtien]

This app failed to loggin when hosting under nginx with a diffrent root path eg
"/xero" instead of "/"

keep getting something like below:
https://login.xero.com/identity/error?errorId=CfDJ8LpFHpnPVChPv4tC90CFl2g9H6bObMBaiP5MRPqPH8yLYyysPB7exsvbTsx63MxP9MHIk27fu8m--kL5YhVHU9iuKbbJ0AEoJWzs1R83sXUkugK553ABftNSgIHKaruFn0zItnTb0LfKSpm53Uu8TGFt7txJoBeQFMl2epttRDExs1Vm4Ae38hb49XUqdBSujC_c_wiWXMbbl4dSrAM-1Tz77NYjeyyw0xqXnQd_lSHsz0gIN5I9gDAbwReh-nFMw-Je_tSb9JnzEstcA1hpiBnlHzbNnYHZ-mfyuj94atcpO_vLFvPy7OM11n5GNF0ss3wRGOahgf6kg3hDBUl7d1LT48UQdp0hDt-z59Y2X09njfrI1kJDH6XLgOfN72TjmQ

[ngvtien]

and as the result we keep on getting the screen below