I have really enjoyed being able to see who is online. However, I have finally traced down some persistent site performance issues to the discourse plugin that provides the display of who is online. If you have ever experienced intermittent display of the maintenance page when no maintenance was announced, I believe you have been affected by this performance problem. Other sites have also seen this plugin causing site performance problems.
Over the past few days, I have been intermittently disabling and enabling this plugin to determine its impact on site performance. It now appears that it will be generally disabled for the future.
You may still occasionally see it pop up; I may temporarily enable this plugin before doing potentially disruptive site maintenance, in order to look for times that will be least disruptive. But at this time I don’t see a way to leave it enabled on an ongoing basis.
Update: I have made a configuration change and have re-enabled Who’s Online. Please comment if you find the site slower to load, or if you see “429” errors (even intermittently) in your browser while browsing Maker Forums normally.