Base filter for only displaying blocked tasks?

[kazerniel]

I want to have a base view where I collect my blocked tasks to make sure nothing gets forgotten, but just putting a ! before the default Not Blocked formula to !list(blockedBy).filter(file(value.uid).properties.status != "done").isEmpty() doesn't seem to do the trick - one of the tasks that does have a blockedBy value, but the blocking task is done, still shows up. Any ideas how to fix it?