问Bootstrap网站上无序列表中的图像不会在Firefox中显示，但会在Safari和Chrome中显示

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                <h3>Expedia Ad for Filter</h3>
                <p>Designed in Photoshop.</p>
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                <h3>GeekWire Ad for Filter</h3>
                <p>Designed in Photoshop & Maya.</p>
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                <h3>Inrix Ad for Filter</h3>
                <p>Designed in Photoshop.</p>
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                <p>Designed in Photoshop.</p>
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                <h3>MSN Ad for Filter</h3>
                <p>Designed in Photoshop.</p>
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                <h3>National Geographic Ad for Filter</h3>
                <p>Designed in Photoshop.</p>
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                <h3>Amber-Allen Ad</h3>
                <p>Designed in Photoshop.</p>
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                <h3>Amber-Allen Ad</h3>
                <p>Designed in Photoshop.</p>
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                <h3>DSF Ad</h3>
                <p>Designed in Photoshop.</p>
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