Is there a visual studio automatic save configuration setting?
Solution 1:
For VS 2019, the Auto Save File extension seems to work as expected.
It saves individual files on lost focus, can save all files when VS loses focus and can also save all after an inactivity delay.
In VS 2015, I used to use NoMorePanicSave2015.
It does an equivalent of Ctrl+Shift+S when Visual Studio loses focus, which saves all your files, including solution and projects.
Solution 2:
Another plugin: CBAutoSave
This extension can automatically save modified documents, projects, and the solution whenever Visual Studio loses focus.
Saving of modified documents is on by default, while automatically saving projects and the solution is not. All options are configurable through the Visual Studio options dialog.