Chrome’s JPEG decoder employs partial inverse discrete cosine transform scaling for images rendered at scales that are fractions of eight, which can cause small icons to appear thicker than expected. The optimization reduces memory usage and speeds decoding by omitting high‑frequency coefficients when the output size is small, reconstructing the image from low‑frequency data before applying standard downsampling. This behavior was observed when a 15‑pixel icon rendered differently in Chrome compared with Firefox. The technique, implemented in Skia through libjpeg‑turbo, decodes the image at a reduced scale with a denominator of eight and then scales to the target size. A Hacker News comment noted that the downstream scaling algorithm also influences the visual result, meaning the degradation results from both partial IDCT and scaling processes. The finding reinforces that JPEG is less suitable for icon assets, where lossless formats such as SVG are preferred.