Peter, please add my +1 vote for this feature.
It seems like a lot of people have been wanting this feature for at least a year on this discussion. A simple google search shows that many others have searched this question from years before. A feature like this is essential during sales seasons, especially right now with Black Friday, Cyber Monday, and Holiday Deals. We want to keep the discounts we were offering before active while allowing our customer to get an additional x% off certain products or entire orders, especially around this time of the year. I'm sure SOMEONE at Shopify could implement this feature pretty quickly...I think we all appreciate you taking the time to inform your team that this is a highly requested function, but it's just frustrating that there's no indication to when we can expect it to be implemented. It seems like this feature should be a core function of any e-commerce platform...And as many have noted before, the usual Shopify response of "There's an app for that" is often an inadequate, ineffective, or completely unrelated solution to many issues brought up, including this one. Even when it does provide a viable workaround certain problems, having to continuously search for third-party apps for functions that should really be built-in to Shopify can be tiring and frustrating.