the target selection dropdown doesn't open with latest tinymce

When I use tinymce version 4.2 the dropdown to select target of a given link is working fine, but on downloading v4 i.e. the latest available in version 4 releases. the same dropdown doesn't open. `Insert/ edit link` plugin opens a dialog box that has the last option to select the target for a link.

Please let me know if you need extra help to reproduce the issue.
