[WetWired]

I messed up my example, so what? The entry still makes it work.

You can make it work both ways if you like, just enter that one, then enter this one:
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<table bgcolor=#CCCCCC><tr><td><font color=#CCCCCC>{param}</font></td></tr></table>
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The spoiler tag forces one to highlight it in order to read it
No

Then, whether or not they enter a color, it will work.