Add the ability to change which monitor a presentation will display on (by default) for the desktop edition while I understand that Only Office isn't intended to be used the same as Libre Office or MS Office it is very much so a valid replacement for such software with the only roadblock in adoption being the lack of ability to change which monitor a presentation slide will display on.
Ideally it would an option like office with a dropdown allowing the ability to change the default monitor.
On a more advanced level the ability to right-click (just an example) on specific slides and display a different slide on different monitors from just one desktop client would be a nice to have.

Cheers in advance.