The newest YCombinator logo (upgraded to SVG in 2023) looks fine on a small screen. But if you zoom or have a large and high resolution screen, you might notice an uneven blue border. The border is 0.375 pixels wide so you might incorrectly think that it's always invisible. Some high density screens automatically zoom by a factor between 2.0 and 3.0 (and perhaps more in the future). In such cases, the tiny border becomes apparent.

The logo can be fixed by tweaking the svg's viewBox:

< ... viewBox="0 0 192 192" ...
> ... viewBox="4 4 188 188" ...