Did you use `> as color code? Would be first thought looking at this.
Nope. Colour codes for that particular mount are
`b`eH`b`i`Eo`i`b`Tr`b`i`Es`i`ee.
If not I'd suggest that the navigation header has a problem with the italic style of the o letter.
I'm not quite sure.. After examining the rest of the mounts on my main account, it seems it's the same with ALL the mounts, no matter where the bold and italics are. That is, the first letter of each mount is where is should be, then the rest is hovering above and away from the nav.