One of the drawbacks of OpenCart is lack of Apply button in forms to save changes and stay on the same page. With this little extension your life will become easier. Apply button will be added to ALL default forms of your store: products, categories, customers, countries, zones, etc.
Simple but great, what a time saver. You never go wrong with this developer!
This extension is helpful however it didn't let other options to work. Possibly, there could be a different extension which might have clashed with this one. It installed properly and worked well however I noticed that continue button at edit order steps got disabled ever since I installed this extension.