Hi Sander
If you refer to the ribbon buttons within the qMediaView web part instead of the ribbon tab inside SharePoint Ribbon on top of the page, then the setting you referred to is not going to hide the ribbon. These ribbon buttons stay there all the time. The setting via Configuration Editor tool can hide the QuickApps ribbon tab inside the SharePoint ribbon on the top of the page. And it only hide the specific tab that QuickApps Web Parts introduce, it will not make the entire ribbon UI disappear.