Created attachment 14636
Screenshot showing the bottom of first copy of the article and the top of the second copy.

Attached:

I have just managed to get the article to open with a single copy, so this is intermittent.

Also, notice the absence of VisualEditor's toolbar. The top of the attached image is the top of the browser window.

I've just loaded it 5 times (with hard refreshes) each in Chrome, Safari and Firefox, without incident – perhaps it could be an odd cacheing issue with the switch-over to the new version?

Can you reproduce still?

I can't reproduce this right now. However, the timestamp on the screenshot is 10:55 a.m. PST (and it had been onscreen for a few minutes before then), and I thought that the deployment was set to start about five minutes after that.

(In reply to WhatamIdoing from comment #4)

I can't reproduce this right now. However, the timestamp on the screenshot
is 10:55 a.m. PST (and it had been onscreen for a few minutes before then),
and I thought that the deployment was set to start about five minutes after
that.

The new version went a little early today, apparently (but only by a few minutes – see https://wikitech.wikimedia.org/wiki/Server_Admin_Log#February_20 where "testwiki to 1.23wmf15 and build l10n cache" at 16:58, though the changes start a couple of minutes before the log), but there were bigger issues involving deployment today that took down all the phase0 wikis (yay). Nothing to do with VisualEditor, but might well have caused random and otherwise inexplicable issues like this.

However, for enwiki changes didn't happen until 21:26, so it /shouldn't/ have been affected, so it's a bit of a mystery. :-(

Marking as WORKSFORME for now.