The /$org/$repo/deployments UI (API /api/repos/org/repo/builds/deployments) is great to find the latest build per deployment target, but in case of a failing builds being able to retrieve the previous deployments would be very useful.
The actual UI makes it hard since you have to go through all builds and search for the promoted builds.
a /$org/$repo/deployments/$target would help to track deployments history.
I would love to have such autocomplete or cache feature on deployment UI when promoting builds.
Users can just select from the drop down list once they key in the target on deployment UI for the first time.