It's on purpose. We have lots of users who needs proxy with fragile proxy. The policy is: if we found all the proxies are disabled or not available, we recognize this as fragile setting, and try the unavailable proxies.
Bug 1549678 Comment 8 Edit History
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It's on purpose. We have lots of users who needs proxy with fragile proxy. The policy is: if we found all the proxies are disabled or not available, we recognize this as fragile proxies, and try those proxies.