Just an FYI for those who aren’t aware of this alternative - for just a couple bucks more you can get the Visonic contact sensors when they go on sale (and they tend to do that regularly) - they are $10 when on sale.
They are natively supported by ST (so easy to pair and get local processing) have a great small/slim profile, and don’t have the issues w/connectivity that the Xiaomi may have.
Worth considering…