Will there be a button for showing changes?
Topic on VisualEditor/Feedback
Yes; right now we're still working out what a "diff" process looks like for users who don't understand (and shouldn't have to learn) wikitext at all - the current diff system is not appropriate. One thing we're looking at is something that steps users through the process of what changed dynamically, but we're at very early days yet. However, we will definitely integrate showing what has changed to editors.
Okay, I get it now. Thanks!