Label letters have uneven vertical offset when scaling

[cguinnup]

Used the label Sandcastle, but disabled FXAA and set scale to 0.5:

You can see the vertical height of the "a"s are off, and the horizontal line in the "e" is very nearly missing. Reproduced in FF and Chrome.

var viewer = new Cesium.Viewer('cesiumContainer');

viewer.entities.add({
    position : Cesium.Cartesian3.fromDegrees(-75.1641667, 39.9522222),
    label : {
        text : 'Philadelphia',
        scale: 0.5
    }
});

[cguinnup]

Similar misalignment also occurs when I set the font size to 14px and 16px, but don't use scaling. This bug combined with #5746 makes it very difficult to display quality text without using a giant font size. Also note that FXAA doesn't solve either case, which I see was discussed as a solution in the blurry text & billboards issues.

[ggetz]

I think this is a duplicate of #8474. Closing this issue to move the discussion there.