Actually, it does work, under limited circumstances. It is a bit strange. If I try to set the masking using the button that lists all the host names, pick one or add one, and try to modify it that way, it does not work. If I visit the site and access the setting from the Tools menu, the masking does work, but I have to visit the site first. Since my natural inclination is to change the setting before visiting the site, I was not seeing the results I expected.
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