diff --git a/.github/workflows/linux-wpt.yml b/.github/workflows/linux-wpt.yml
index 9ae9ba2b01f..3262dba96c4 100644
--- a/.github/workflows/linux-wpt.yml
+++ b/.github/workflows/linux-wpt.yml
@@ -30,15 +30,15 @@ jobs:
         chunk_id: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20]
     steps:
       - uses: actions/checkout@v3
-        if: github.event_name != 'issue_comment'
+        if: github.event_name != 'issue_comment' && github.event_name != 'pull_request_target'
         with:
           fetch-depth: 2
       # This is necessary to checkout the pull request if this run was triggered
       # via an `issue_comment` action on a pull request.
       - uses: actions/checkout@v3
-        if: github.event_name == 'issue_comment'
+        if: github.event_name == 'issue_comment' || github.event_name == 'pull_request_target'
         with:
-          ref: refs/pull/${{ github.event.issue.number }}/head
+          ref: refs/pull/${{ github.event.issue.number || github.event.number }}/head
           fetch-depth: 2
       - uses: actions/download-artifact@v3
         with:
diff --git a/.github/workflows/mac-wpt.yml b/.github/workflows/mac-wpt.yml
index 28940a2fab5..5c01bc4d6a4 100644
--- a/.github/workflows/mac-wpt.yml
+++ b/.github/workflows/mac-wpt.yml
@@ -28,15 +28,15 @@ jobs:
         chunk_id: [1, 2, 3, 4, 5]
     steps:
       - uses: actions/checkout@v3
-        if: github.event_name != 'issue_comment'
+        if: github.event_name != 'issue_comment' && github.event_name != 'pull_request_target'
         with:
           fetch-depth: 2
       # This is necessary to checkout the pull request if this run was triggered
       # via an `issue_comment` action on a pull request.
       - uses: actions/checkout@v3
-        if: github.event_name == 'issue_comment'
+        if: github.event_name == 'issue_comment' || github.event_name == 'pull_request_target'
         with:
-          ref: refs/pull/${{ github.event.issue.number }}/head
+          ref: refs/pull/${{ github.event.issue.number || github.event.number }}/head
           fetch-depth: 2
       - uses: actions/download-artifact@v3
         with: