I just updated my board, a disabled live board, and I had no problem.
However, I miss one thing and I think one more step could be added to the update package, before continuing the update, and what I mean is to inform the user about what each step does, but also have one last chance to cancel the update should one wants to abort the update process.
Because during the update I thought about to cancel the update, but wasn't sure of how to do that without causing an issue and that's something I don't want to fiddle with if I can avoid that. Sure, I could simply close Firefox or select another tab then remove the tab I had for updating my board.
My thanks goes to eveyrone who have worked hard to make this happen.