When you are presenting a presentation with multiple animations per slide, competing presentation editors show the next animation/slide in presenter view. If the presenter is someone like me who shows data figures section by section to walk the audience through it by removing white boxes with animations, its impossible to see what's going to be shown on click without this. Onlyoffice currently just has a slide list with a scroll bar, which makes it unusable for when I give seminars. All this would take is a small rendered preview of the next slide/animation in the corner of presenter mode, just so I'll have a visual reminder of what happens when i click next slide.