After hours of research I am not able to find a way to remove the fly-out menu from the quick launch bar without changing the master page. I tried by changing the Tree View settings, as well as quick launch bar settings. None were successful. Is there a way to apply JQuery script into a script editor web part. For an example, please see below. Thanks for any help.
Non Fly-out Menu
Update Further research... if I add the following to a script editor What do you think?
<style type="text/css"> .ms-core-listMenu-item </style>