diff --git a/.github/workflows/phpunit-mysql.yml b/.github/workflows/phpunit-mysql.yml
index 441e79b1205e1..cd20ae4a61de0 100644
--- a/.github/workflows/phpunit-mysql.yml
+++ b/.github/workflows/phpunit-mysql.yml
@@ -14,7 +14,7 @@ on:
 
 jobs:
   phpunit-mysql:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
 
     strategy:
       # do not stop on another job's failure
diff --git a/.github/workflows/phpunit-sqlite.yml b/.github/workflows/phpunit-sqlite.yml
index ae33b8e83922e..656ff6d13bfa5 100644
--- a/.github/workflows/phpunit-sqlite.yml
+++ b/.github/workflows/phpunit-sqlite.yml
@@ -23,7 +23,7 @@ env:
 
 jobs:
   phpunit-sqlite:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
 
     strategy:
       matrix: