[gentoo-user] Howto use user CSS with Firefox?

[Robin Atwood]

Many web sites are badly designed in that that they hard-code text input 
fields with a black font but inherit the background colour from your desktop, 
so if you have a suitably Gothic light-on-dark colour scheme you cannot read 
your input. I have solved this with KDE Konqueror by supplying a user css 
page but, for those occasions when you have to use it, I want to do the same 
thing with Firefox. A quick google reveals the presence of userContent.css in 
your profile, so I added my rules, eg,

html->body {
  background-color: white;
  color: black;
}

input {
  background-color: #E1E7FD;
  color: black;
}

but it makes absolutely no difference. Anybody had any luck with this?

TIA
-Robin
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