Issue #3387656: Package name schema regex fails on 11.x

package_manager/config/schema/package_manager.schema.yml

@@ -4,7 +4,7 @@ package_name:
   constraints:
     Regex:
       # @see https://getcomposer.org/schema.json
-      pattern: '/^[a-z0-9]([_.-]?[a-z0-9]+)*/[a-z0-9](([_.]|-{1,2})?[a-z0-9]+)*$/'
+      pattern: '/^[a-z0-9]([_.-]?[a-z0-9]+)*\/[a-z0-9](([_.]|-{1,2})?[a-z0-9]+)*$/'
 
 package_manager.settings:
   type: config_object

[Ted Bowman]

So this this is actual fix. Just needed to escape the /

[Ted Bowman]

For future reference I used this site to debug the regex https://regex101.com/