When visiting the chat room section of Stack Exchange you might have come across a room that is called 'Spring Cleaning' and wondered what it is used for. This post should serve as a brief rundown of everything necessary to know.
Let's start with some historic context. A few years ago, while it was spring in the northern hemisphere, we wanted to do some coordinated site-cleanup, and hence Spring Cleaning was born. And in that linked question, a lot more information is collected.
After the event was over, we kept on going cleaning up in the background. We have simplified the procedure so everybody can more easily chime in. See below for our "ground rules". During the last years we've cleaned up most of the homework tag questions and kept an eye on new ones coming in.
How does it work? ("Ground rules")
With this chat room we're aiming to improve the quality of the Q&A. That means a lot of editing, up-voting, reopening, but occasionally also down-voting and manually deleting. In that way, the chat room also serves as a permanent record for what decision was made, by whom, and when. We want to have the process as transparent as possible.
We care about old stuff in there. Basically everything that fell through the cracks when the automatic cleanup algorithms were applied (see main meta for more details), or nobody has looked at for quite a while. So, we don't deal with anything newer than a month old, preferably at least a year. The younger questions are best dealt with by the community at large and there are quite a lot of tools for them to deal with it. (Obviously, edits are okay, no matter when the post was written.)
Cleaning up when necessary, as (occasionally) there is content that's simply not worth keeping. Our main guideline to delete a question is to require at least two people agreeing on removing it. (These don't necessarily have to be moderators.) Often, one of those two people has been either Orthocresol or Martin, by way of presence and executive power, but next time it could be you and you (*points a few fingers around*)!
Now that we've gotten that out of the way, the process is as follows: Q&As that should be reviewed are posted as a single link in one message and what you propose to do in another. That allows them to be expanded ("oneboxed") in SE chat rooms. When the review is done (deleted, edited, or otherwise), we usually edit the post to remove the onebox. That lets us quickly see what hasn't been looked at, yet. The usual user cannot edit old messages, but a moderator can. So if you need an edit to a message, ping one of them and they'll do it.
If you want to agree or disagree, link your chat message to the one with the link.
Fair warning though, pings are liberal in that chat room, so you'll have to expect a full inbox when you participate.
We often have a current query running, you'll find that in the starred messages section, and it's often pinned also. There we keep a count on the questions to be dealt with, too.
And that's pretty much it. If you have more questions, ask below or in the chat.