Atom logo gets cut off in Discourse header


The “M” in the Atom logo in the Discourse header is chopped off. This is in Firefox Nightly on Linux.


I don’t see it in either Firefox 29.0 or Chrome 34.0 (for Mac). Wouldn’t this be a bug in Firefox?


Yup, seems like a quirk in their bitmap smoothing function. With a sharp eye you notice it a bit in chrome as well but it slightly lighter.


Huh, this does actually look like a rendering bug. In the CSS I see max-height: 40px. When I change that rule to width: 160px (which is visually the same size), the strange rendering goes away.


Sure, any value that doesn’t gives a division by 3 of the width ^^

The logo is 580x120px, forcing it to 40px height will resize the width to: 580 * (40 / 120) > 580 * 1/3 > 193.3333...
I guess they changed the way they round values when downsizing a bitmap and doesn’t works well with division by 3.