u/atpetersin r/kubernetes • Recommends
On “Kubernetes 1.18 Will Embrace Sidecars: Why It Matters”
You can use sidecars, but you can't expressly call them out as such and they have a slight technical issue for some regarding when they start/stop.
The link that /u/csnfickas posted explains it a bit more. This is a link from the issue that tries to explain the proposal/concept a little more for the feature [video
/edit: Just read your edit.