Assertion:
Netscape 4.x error condition bug: if a BGCOLOR and BACKGROUND attribute have been specified for the row, and the URL to the image fails to load, the bgcolor should be used instead. Netscape 4.x does that for a moment, but then this changes to a block only the size of the broken image placeholder with the specified BGCOLOR in the upper, left corner of each of the cells in the row.

Reference: Plain TABLE; background="wrench.gif", bgcolor="green" on row 2:
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TD Cell 1 TD Cell 1
TD Cell 1 TD Cell 1		 TH Cell 2 TH Cell 2
TH Cell 2 TH Cell 2
TH Cell 3 TH Cell 3
TH Cell 3 TH Cell 3		 TD Cell 4 TD Cell 4
TD Cell 4 TD Cell 4
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Reference: Plain TABLE; No background, bgcolor="green" on row 2:
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TD Cell 1 TD Cell 1
TD Cell 1 TD Cell 1		 TH Cell 2 TH Cell 2
TH Cell 2 TH Cell 2
TH Cell 3 TH Cell 3
TH Cell 3 TH Cell 3		 TD Cell 4 TD Cell 4
TD Cell 4 TD Cell 4
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Reference: Plain TABLE; valid background="wrench.gif", no bgcolor on row 2:
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TD Cell 1 TD Cell 1
TD Cell 1 TD Cell 1		 TH Cell 2 TH Cell 2
TH Cell 2 TH Cell 2
TH Cell 3 TH Cell 3
TH Cell 3 TH Cell 3		 TD Cell 4 TD Cell 4
TD Cell 4 TD Cell 4
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Test: Plain TABLE; Invalid background="noexist.gif", no bgcolor on row 2:
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TD Cell 1 TD Cell 1
TD Cell 1 TD Cell 1		 TH Cell 2 TH Cell 2
TH Cell 2 TH Cell 2
TH Cell 3 TH Cell 3
TH Cell 3 TH Cell 3		 TD Cell 4 TD Cell 4
TD Cell 4 TD Cell 4
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Test: Plain TABLE; Invalid background="noexist.gif", bgcolor=green on row 2:
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TD Cell 1 TD Cell 1
TD Cell 1 TD Cell 1		 TH Cell 2 TH Cell 2
TH Cell 2 TH Cell 2
TH Cell 3 TH Cell 3
TH Cell 3 TH Cell 3		 TD Cell 4 TD Cell 4
TD Cell 4 TD Cell 4
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