/proc/4/root/proc/thread-self/root/proc/thread-self
This explorer reads the filesystem of the server it runs on, so /workspace/user isn't present here. Browsing and the terminal still work against this server's own disk from /.
11:devices:/10:perf_event:/9:memory:/8:pids:/7:cpuset:/6:cpu,cpuacct:/5:blkio:/4:freezer:/3:hugetlb:/2:net_cls,net_prio:/1:name=systemd:/