Coverage. With filtered URL 

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@[example](video-123)
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<div class="block-embed block-embed-service-example"><iframe type="text/html" src="https://example.com/embed/video-123/42?a=example&b=video-123&c=block-embed" frameborder="0" webkitallowfullscreen mozallowfullscreen allowfullscreen></iframe></div>
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@[example](x)
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<div class="block-embed block-embed-service-example"><iframe type="text/html" src="https://example.com/embed/x/42?a=example&b=x&c=block-embed" frameborder="0" webkitallowfullscreen mozallowfullscreen allowfullscreen></iframe></div>
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