server.php exits silently when syntax error in plugin
When there is a syntax error in any plugin loaded, server.php exits silently, and lock does not get removed, and log gets filled with "lock already present"-like messages. There should be something to do to detect that kind of failure and at least report it clearly. Worse: I had to add a lot of log messages in server.php itself to detect where it actually failed.
You might argue that it is developer's responsibility to check its plugins for syntax (php -l), but while actually developing the plugin, it might happen far more than needed, and the problem is then really difficult to track.