Any production dependencies on non-`master` branches?

[kili-ilo]

This is similar to selkies-project/selkies#21

I'm planning to delete every branch other than master (and dev, though it's currently unused), since they all seem abandoned (chc-docs, istio-sidecar, xpra-4.4-r30771-html5-4.5.2), or are replaced by a tag (v1.4.0). I've renamed those 4 branches to add a delete-me/ prefix, in anticipation of their deletion. Do we know of any production/live environments that depend on those branches?