Here I was thinking program smart enough to recognize by extensions but guess not.

I changed from .txt, .php etc to *.php,*.html etc and it works.

Moral..don't over estimate your software!

Here are my settings as image.
Thanks

So what is your settings? Please post screenshot.
Do you have Edit or Open configured for double-click?

Recent update broke external text editor use.
I have settings to use Note++ as my editor. The icon is correct but clicking any file only opens the internal editor. Have checked settings three times and they are correct but still refuses to use my external editor.