In fact, why don't they warn a webmaster about it before blocking it? Say, "Hey, you have a bad file here. If you don't want us to tell Firefox to block your site, please remove it immediately. Thanks!"
Well, for one thing, they have no idea how long it's gonna be before the webmaster replies/acts on it and why should people be exposed to it while Google waits for them?
That part of it at least is good on Google's part.
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