Factorio Forums

It transfers every blueprint from the library to your inventory, completely destroying whatever organization you had done. I can't see any reason why you would ever want to do this. Disabling it seems like the best course of action to avoid accidents, as someone (not me) lost their entire blueprint library by doing this, and then reloading a save thinking it would revert.

I also think that taking a blueprint from the library to your inventory should copy rather than removing it, but that's a separate issue and probably needs more discussion around it.