Apple Safari 17’s hidden gems: JPEG XL and font resizing
3 mins read

Apple Safari 17’s hidden gems: JPEG XL and font resizing

Apple’s recently announced Safari 17 brings several major updates that promise to improve user experience and web page load times.

Two new features of Safari 17, unveiled at the annual Worldwide Developers Conference (WWDC23), are JPEG XL support and expanded font sizing capabilities.

As Safari evolves, these updates underscore the ever-changing landscape of web development and the importance of adaptability.

JPEG XL: A Game Changer for Page Speed ​​Optimization

One of Safari 17’s most notable features is support for JPEG XL, a new image format that balances image quality and file size.

JPEG XL allows existing JPEG files to be recompressed without data loss while significantly reducing their size – by up to 60%.

Page loading speed is a crucial factor that search engines consider when ranking websites. With JPEG XL, publishers can drastically reduce the file size of images on their websites, potentially resulting in faster page loads.

Additionally, support for progressive loading in JPEG XL means users can start viewing images before the entire file has finished downloading, improving the user experience on slower connections.

This benefits websites that target regions with slower internet speeds, improving the user experience and potentially lowering bounce rates.

Font Size Adjustment: Improve user experience and consistency

Safari 17 expands the capabilities of font-size-adjusta CSS property that ensures that the visual size of different fonts remains consistent across all possible combinations of fallback fonts.

By allowing developers to pull the size metric from the main font and apply it to all fonts, the from-font value can help websites maintain a consistent visual aesthetic, which is critical to user experience.

Conversely, the two-value syntax offers more flexibility in customizing various font metrics and supports a wider range of languages ​​and design options.

Websites with consistent and clear text display, regardless of the font used, are likely to provide a better user experience. A better experience could lead to longer visits and higher engagement.

Rethink SEO strategies with Safari 17

In light of these developments, SEO professionals may need to adjust their strategies to take full advantage of Safari 17’s capabilities.

This could include:

  • image optimization: Since JPEG XL is supported, SEO professionals may need to consider reformatting their website images to this new format.
  • site design: The extended possibilities of font-size-adjust could require a rethinking of design strategies. Consistent font sizes across languages ​​and devices can improve CLS, one of Google’s most important web features.
  • performance tracking: SEO professionals will need to closely monitor the impact of these changes on site performance metrics once the new version of Safari rolls out.

In total

Apple’s Safari 17 brings new features that offer opportunities to improve several website performance factors critical to SEO.

Detailed documentation on these Safari 17 updates is available on the official WebKit blog for those who want to delve deeper into these features.


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