On mediawiki.org, I tried to edit the Extension:DonationInterface mess using VE. I had forgotten to log in. Things went fine (other than copy + paste not working), but when I went to save I learned "You are blocked from making edits."
This is a discouraging message to get after having made edits.
Are you sure your IP address wasn't actually blocked? WMF office's IP was globally blocked at some point (dunno if still is) to make sure that WMF employees always edit logged in :)
Bah, this is silly. The information that you're blocked is normally displayed in the "edit notices" area, both in VE and in wikitext editor, but when it's your first time making a VE edit, the notices are hidden behind the "welcome dialog" and disappear when you close it. That's a bug.
Change 185393 had a related patch set uploaded (by Bartosz Dziewoński):
Wait with showing edit notices until after the welcome dialog is closed
Change 185393 merged by jenkins-bot:
Wait with showing edit notices until after the welcome dialog is closed