While there is a slight difference in workorder (copied components before trimming), there are a few differences with the desktop app (and iPad, for that matters) that really impacts the workflow:
Desktop app:
Webapp:
Besides the highlight difference when entering the dialog (Desktop=highlighted/selected with the original definition name, WebApp needs an additional click to enter) the main problem is that you won’t get the 'Replace definition…" dialog in the web (and in iPad, it doesn’t work properly, btw) version.
It should definitively work the same across platforms, IMO
link to iPad version: