--- a/tests/test-rhg.t	Thu Mar 17 12:27:40 2022 +0100
+++ b/tests/test-rhg.t	Fri Mar 18 17:39:06 2022 +0100
@@ -391,3 +391,17 @@
   $ echo "*:required = yes" >> $HGRCPATH
   $ rhg files
   a
+
+We can ignore all extensions at once
+
+  $ echo "[extensions]" >> $HGRCPATH
+  $ echo "thisextensionbetternotexist=" >> $HGRCPATH
+  $ echo "thisextensionbetternotexisteither=" >> $HGRCPATH
+  $ $NO_FALLBACK rhg files
+  unsupported feature: extensions: thisextensionbetternotexist, thisextensionbetternotexisteither (consider adding them to 'rhg.ignored-extensions' config)
+  [252]
+
+  $ echo "[rhg]" >> $HGRCPATH
+  $ echo "ignored-extensions=*" >> $HGRCPATH
+  $ $NO_FALLBACK rhg files
+  a