diff --git a/.github/workflows/upgrade-develop-testing.yml b/.github/workflows/upgrade-develop-testing.yml
index edb57bc8d6..7b7d0734f4 100644
--- a/.github/workflows/upgrade-develop-testing.yml
+++ b/.github/workflows/upgrade-develop-testing.yml
@@ -63,13 +63,17 @@ jobs:
         php: [ '7.2', '8.4' ]
         db-type: [ 'mysql' ]
         db-version: [ '5.7', '8.4' ]
-        wp: [ '6.5', '6.6', '6.7' ]
+        # WordPress 4.9 is the oldest version that supports PHP 7.2.
+        wp: [ '4.9', '6.5', '6.6', '6.7' ]
         multisite: [ false, true ]
 
         exclude:
           # The PHP <= 7.3/MySQL 8.4 jobs currently fail due to mysql_native_password being disabled by default. See https://core.trac.wordpress.org/ticket/61218.
           - php: '7.2'
             db-version: '8.4'
+          # WordPress 4.9 does not support PHP 8.4.
+          - php: '8.4'
+            wp: '4.9'
     with:
       os: ${{ matrix.os }}
       php: ${{ matrix.php }}
diff --git a/src/wp-admin/includes/update-core.php b/src/wp-admin/includes/update-core.php
index 2c05d16188..b249c11275 100644
--- a/src/wp-admin/includes/update-core.php
+++ b/src/wp-admin/includes/update-core.php
@@ -1199,7 +1199,7 @@ function update_core( $from, $to ) {
 		}
 
 		// Add a warning when required PHP extensions are missing.
-		if ( $missing_extensions->has_errors() ) {
+		if ( ! empty( $missing_extensions->errors ) ) {
 			return $missing_extensions;
 		}
 	}