The guide says "Letter spacing: -20", but I think that the layout is really "Letter spacing: -0.20" (at least in inkscape). @Serhio Magpie can you confirm or refute my suspicion?
Topic on Manual talk:MediaWiki logo guidelines
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Hi. I think we forgot to clarify that these are dimensions from Photoshop. Actually letter-spacing is equal to <code>-0.02em</code> in CSS. Not sure how it would be in Inkscape.
Inkscape seems to use px units for letter spacing by default which is obviously not ideal for repeatable standards at different text sizes.
Yeah. According to online converters, this is -0.92px relative to 46px font size, what i used in psd.