diff --git a/.github/workflows/go.yml b/.github/workflows/go.yml
index 5d898ca66ab..81ac28658cc 100644
--- a/.github/workflows/go.yml
+++ b/.github/workflows/go.yml
@@ -181,5 +181,5 @@ jobs:
         config-file: 'hack/.md_links_config.json'
     - name: Markdownlint
       run: |
-        sudo npm install -g markdownlint-cli
+        sudo npm install -g markdownlint-cli@0.31.1
         make markdownlint
diff --git a/docs/antrea-network-policy.md b/docs/antrea-network-policy.md
index 84b77153788..e9c367b07fa 100644
--- a/docs/antrea-network-policy.md
+++ b/docs/antrea-network-policy.md
@@ -802,7 +802,7 @@ status:
       lastTransitionTime: "2021-01-29T20:21:48Z"
 ```
 
-There are a few __restrictions__ on how ClusterGroups can be configured:
+There are a few **restrictions** on how ClusterGroups can be configured:
 
 - A ClusterGroup is a cluster-scoped resource and therefore can only be set in an Antrea
 ClusterNetworkPolicy's `appliedTo` and `to`/`from` peers.