Windows 10: how to always use this app to open files w/o filename extension?

When you open file w/ extension for the 1st time you see this:

When you open file w/o extension for the 1st time you see this:

So, where is "Always use this app to open files w/o filename extension"? Confused.

Example: the end user needs to open all extensionless files in a text editor. How to do that in Windows 10?

Solution 1:

Apps that can open a file by pointing to a file must have extensions that point to the app. There is not any way around this.

What you can do, what I do, is use Windows File Explorer to point the file, Right Click and then use the Open With selection. That will allow you to select an app like Notepad, UltraEdit or like app.