Use CSS. E.g.
.Header-logo {
display: none;
}
.Header-title a {
display: inline-block;
width: 82px;
height: 30px;
background: url(/assets/logo-xxxxxxxx.png) top left/contain no-repeat;
}
That also has the advantage that you can use the full 36px available instead of 30px with the header image vertically centred.
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