QBlocker is intended to avoid accidentally closing an application that you are working with. The app is installed easily and requires a few initial steps before it becomes fully functional, which includes giving it the necessary authorization to mess with your system.
The application has been designed in such a way that you hardly need to interact with its interface. It runs in the background instead and pushes you to hold down the Command + Q keys a little longer if you really want to quit the active window. The only sign that QBlocker is working is its small icon in the Menu Bar, from which you can access some configuration options.
Good news is that the app lets you create a list of exceptions, that is, those apps you would like to be able to quit immediately without any interference by QBlocker. Likewise, it is possible to set the exact time that the active application will remain there before quitting.
In general, QBlocker is great if you commonly press the wrong keys, which may lead to accidentally closing the active application. QBlocker is light and open source, so trying does not cost you a dime. Unfortunately, it crashed sometimes when I tried to access the Menu Bar menu.