When input field on focus but no input entered, the placeholder text should have shown. But actually it is clear. See page 3 of https://bugzilla.yoctoproject.org/attachment.cgi?id=1754.
The design document just explains the default Twitter Bootstrap behaviour. It works for me, so I am wondering if this is a browser-specific issue. Yuan: could you tell me which browser you are using?
Ubuntu 12.04 32bit Firefox 11.0
Since this is a very minor thing, which is probably related to browser support for Twitter Bootstrap features, I am going to set it to resolved / won't fix. I hope that's ok.
Verified.