Update

vendor/tailscale.com/feature/useproxy/useproxy.go

@@ -1,4 +1,4 @@
-// Copyright (c) Tailscale Inc & AUTHORS
+// Copyright (c) Tailscale Inc & contributors
 // SPDX-License-Identifier: BSD-3-Clause
 
 // Package useproxy registers support for using system proxies.
@@ -10,6 +10,9 @@ import (
 )
 
 func init() {
+	if !feature.Register("useproxy") {
+		return
+	}
 	feature.HookProxyFromEnvironment.Set(tshttpproxy.ProxyFromEnvironment)
 	feature.HookProxyInvalidateCache.Set(tshttpproxy.InvalidateCache)
 	feature.HookProxyGetAuthHeader.Set(tshttpproxy.GetAuthHeader)