diff --git a/.github/workflows/cron.yml b/.github/workflows/cron.yml
index 773fb4c..598199a 100644
--- a/.github/workflows/cron.yml
+++ b/.github/workflows/cron.yml
@@ -6,6 +6,7 @@ name: --pre Test
 on:
   schedule:
     - cron: '0 */12 * * *'  # every 12 hours
+  pull_request: {}
   workflow_dispatch:
 
 jobs:
@@ -17,7 +18,7 @@ jobs:
       fail-fast: false
       matrix:
         python-version: ['3.8', '3.9', '3.10']
-        platform: [ubuntu-latest, macos-latest, windows-latest]
+        platform: [ubuntu-latest]
 
     steps:
       - uses: actions/checkout@v3