diff --git a/.github/workflows/master-latest.yaml b/.github/workflows/master-latest.yaml
index 34f37af..00c974e 100644
--- a/.github/workflows/master-latest.yaml
+++ b/.github/workflows/master-latest.yaml
@@ -2,7 +2,11 @@ name: master-latest
 
 on:
   push:
-    branches: [ master ]
+    branches:
+      - master
+  pull_reuqest:
+    branches:
+      - master
 
 jobs:
   multiarch-to-dockerhub-latest:
diff --git a/Dockerfile b/Dockerfile
index e6e45c7..284fe26 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -92,7 +92,7 @@ ENV MANIFEST_CACHE_SECONDARY_TIME="60d"
 
 # The default cache duration for manifests that don't match either the primary or secondary tiers above.
 # In the default config, :latest and other frequently-used tags will get this value.
-ENV MANIFEST_CACHE_DEFAULT_TIME="1h"
+ENV MANIFEST_CACHE_DEFAULT_TIME="1m"
 
 # Should we allow actions different than pull, default to false.
 ENV ALLOW_PUSH="false"