diff --git a/Gemfile.lock b/Gemfile.lock
index ccf722d63c9..895bf6028fb 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -84,7 +84,7 @@ GEM
     html-pipeline (2.7.2)
       activesupport (>= 2)
       nokogiri (>= 1.4)
-    html-proofer (3.8.0)
+    html-proofer (3.9.1)
       activesupport (>= 4.2, < 6.0)
       addressable (~> 2.3)
       colorize (~> 0.8)