I'm using PCManFM 1.1.2 and if an object is removed by an external command PCManFM does correctly remove the object from the window but after pressing F5 to refresh the directory PCManFM crashes. I have made a backtrace with gdb and done the following steps:
1. Killing the old instance of pcmanfm (to disable the desktop mode) and creating a new process with gdb.
2. Navigating to /media where the directory sr0 exists (a mounted device).
3. Ejecting the device caused a script to unmount it and removed the directory sr0.
4. PCManFM correctly removed the directory sr0 from the window.
5. After pressing F5 PCManFM crashes.