First, svirt_sandbox_file_t is superseded by container_t
But more importantly, the following Salt block fails on Equatower:
selinux_context_etherpad_data:
selinux.fcontext_policy_present:
- name: /srv/etherpad
- sel_type: svirt_sandbox_file_t
selinux_context_etherpad_data_applied:
selinux.fcontext_policy_applied:
- name: /srv/etherpad