diff -r f77e4daaf612 -r 005ae1a343f8 rust/rhg/src/main.rs
--- a/rust/rhg/src/main.rs	Fri Dec 03 14:36:40 2021 +0100
+++ b/rust/rhg/src/main.rs	Tue Nov 16 11:53:58 2021 +0000
@@ -593,7 +593,8 @@
     }
 }
 
-const SUPPORTED_EXTENSIONS: &[&[u8]] = &[b"blackbox", b"share"];
+const SUPPORTED_EXTENSIONS: &[&[u8]] =
+    &[b"blackbox", b"share", b"sparse", b"narrow"];
 
 fn check_extensions(config: &Config) -> Result<(), CommandError> {
     let enabled = config.get_section_keys(b"extensions");