I think it's confirmed. NWjs is saving to the IndexedDB folder. Testing by deleting this only folder in middle of another files.
I also found this topic that teaches how to make a "copy" of the save in a custom location, but using the default "Save State", not Local Storage.
https://www.construct.net/en/tutorials/save-load-game-specific-1054
Anyway, it is likely that I can do it in a similar way if necessary, or just save the "array save content" in a file with NW.js plugin.
Thanks Mikal for your suggestions, I'll probably work on this way and test your plugin on future :)
Friend, were you able to use steam cloud together with local storage?
I've been trying this all day and here he doesn't read the files in the cloud.
By the way, I would like to give you a tip (I intend to follow her soon)
2 users of my game, reported problems with the save system not working. Both manual and automatic.
I was never able to reproduce this bug, but I am studying changing the save system, as I believe that these users may be having problems with the way the local storage works.
However, I can't do that today, so I would like to make steam cloud work with local storage. Can you tell me how you did it to succeed?