Due to a bug in our release system we've been shipping beta releases to editor.construct.net since our first stable release r71. This should now be fixed, so from this build onwards, editor.construct.net will only serve the latest stable release. To use beta releases you'll need to visit its dedicated URL, e.g. editor.construct.net/r72. We'll include reminders in the next few beta releases about this. Later down the line we will probably also add a separate update system for those of you who'd like to opt-in to beta updates as well.
As for this build, there's nothing new in this specific release - we're simply transferring r84 to the stable channel. This is to make sure there aren't any last-minute breaking changes in a stable update. In case you missed them, you can see the full release notes for past releases on the releases page.