Restore backups slow, make it clearer

[flaviozluca]

But think about it, it works fine for many accounts... What if we just put some disclaimer or rule. If account has over x folders, we can't guarantee and there's a restore fee? We could put that in our contacts. But I would love to keep this feature, it's so important.

Is it too complicated to change the system, so that it doesn't have to go through all the folders? Even if it takes long, we can do the 1st option temporarily until we can improve that, in the future...

#785630