I agree that the safest thing to achieve the goal is to exclude exact matches on prefix and prefix+slash. The required modification looks small.

Is this something you want? If so I'll open a PR.

+++	prefixSet := sets.NewString(keepPathPrefixes...)
	for path, pathItem := range sp.Paths.Paths {
		if !prefixes.HasPrefix(path) {
			continue
		}
+++		if !strings.HasSuffix(path, "/") {
+++			continue
+++		}
+++		if !prefixSet.Has(path) {
+++			continue
+++		}
		ret.Paths.Paths[path] = pathItem
	}

From a quick glance I don't think it's correct but seems close. Here's a useful test case

FilterSpecByPathsWithoutSideEffects([]{"/apis/group/v1beta1/"}, []{"/apis/group/v1"}, ...} should return "" because despite v1 being a prefix of v1beta1, we should really be matching for "/apis/group/v1/...".

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/lifecycle stale

The Kubernetes project currently lacks enough active contributors to adequately respond to all issues.

This bot triages un-triaged issues according to the following rules:

• After 90d of inactivity, lifecycle/stale is applied
• After 30d of inactivity since lifecycle/stale was applied, lifecycle/rotten is applied
• After 30d of inactivity since lifecycle/rotten was applied, the issue is closed

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• Mark this issue as fresh with /remove-lifecycle rotten
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/lifecycle rotten

I saw this issue is rotten, so I'm trying to give it a go: #520. First time opening a PR, please let me know if I missed anything.