I fixed a few bugs over the weekend. While deploying the new version, I noticed that some studio pages didn't work. (The web server was crashing shortly after serving my page.) In the course of investigating that I upgraded some software, rebooted, and… the machine didn't come back up.

Thanks to the technicians at my hosting provider, that got sorted out this morning. It was a minor network configuration issue — the name for my machine in /etc/hosts didn't match the name in /etc/sysconfig/network. It was a big scare (shit; what if the machine died? when was my last backup?) but luckily it turned out to be relatively simple.

Regarding the original problem that caused crashing, I haven't fixed it, but I disabled the category tree widget which seemed to be the source. So if you use that in your studio pages it will simply not show up for now.