HR displayed different in Firefox

Question

As the title explains, I have a little problem displaying a

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line.

In IE 7, 8, 9, Google Chrome, Opera Safari, all the same, no problem just one d

Answer 1

This is related to the foreground color, Kevin Lynch's fix did not work for me on a page with a light grey (#d1d1d1) body background. Changing the HR colour to white does work and it now appears as etched.

hr {color: #ffffff;}

In practice the HR just needs to be any shade that is lighter than the background, so white will always work.