GoKawiilFirefox 156 cuts JPEG decoding memory use by 20x, speeds up PDF viewer 45%
Mozilla's Firefox 156 release improves large JPEG handling by using libjpeg-turbo's IDCT scaling during decoding instead of loading full-size images first, cutting memory use up to 20 times and doubling decode speed. The update also makes the built-in PDF.js viewer start up to 45% faster by loading its background worker earlier, and expands sponsored address bar suggestions to France, Germany and Italy. Firefox 157, due in about two weeks, is expected to add support for the JPEG XL image format.
GoKawiil's interpretation of the reporting above, not reported fact.
These are largely invisible efficiency gains rather than user-facing features, reflecting Mozilla's twice-monthly release cadence focused on incremental performance polish. The looming addition of JPEG XL support is notable because Firefox would join Safari as one of the few major browsers backing the format after Chrome dropped it in 2022, potentially reviving its adoption prospects.
- Firefox 156 slashes memory use and doubles speed for large JPEG decoding via libjpeg-turbo's IDCT scaling.
- The built-in PDF viewer now starts up to 45% faster by pre-loading its background worker.
- Firefox 157 is expected to add JPEG XL support, a format only Safari currently backs among major browsers.
Source: news.slashdot.org — Posted, 2026-09-16
Published there as: “Firefox Touts Lower CPU Use for Large JPEGs, Faster PDF Viewer Startup (and AI Controls)”
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