# ( ) & | are supported. if binary operator is missing the last
# operator in same scope is repeated, or "|" if none used in scope
# yet. client config entries can be used as rights by prefixing them
-# with "client/". If missing, access will be granted.
+# with "client/".
+# ! is supported to negate the subsequent expression.
+# If missing, access will be granted.
#
# Example:
# client/feature_default_enabled | ( feature & system )