Don't re-generate assets when opening file

[hedgefield]

For files that have Generate Image Assets enabled, it would be great if they wouldn't auto-generate each time you open the document (or at least make that a checkbox).

I store different-sized versions of an image in artboards in my psds for social media use etc, but once they're generated I move those files somewhere else, and I don't want to keep the -assets folder, but every time I open the psd again it recreates it.