Last November, Google engineers submitted a patch, saying the decisionIn Chrome 110Remove experimental support for JPEG-XL image format.At that time, Mozilla did not clearly express its attitude towards JPEG-XL, but it continued to provide support in the nightly version of Firefox. JPEG-XL is available as an optional feature.

After months of discussions, Firefox is finallySureSupport for JPEG-XL:neutral.

At the time, Google engineers explained why support for JPEG-XL was being removed from Chrome, including:

• Flags and code in the experimental stage should not be kept indefinitely
• The overall ecology lacks interest in the JPEG-XL format, and it is difficult to continue to promote experiments
• The new image format doesn’t provide enough incremental benefit over the existing ones that there’s no reason to enable it by default
• Reduces maintenance burden by removing related code, allowing developers to focus on improving existing formats in Chrome

Mozilla engineer Martin Thomson recentlypublishedComments on supporting the JPEG-XL image format:

After a lot of consultation, we finally came to the final conclusion:Be neutral on JPEG-XL.

It’s a clear acknowledgment that adding support for new formats comes with a cost, not just for us (adding, securing, and maintaining code is not easy), but for the web industry as a whole. In general, fewer formats is better for the Web, because it reduces the complexity of authoring and delivering content. Of course, the developer will provide as many formats as possible within the scope of meeting the needs of users and developers.

Developers will make a comprehensive evaluation based on the features provided by the format, overall performance and other dimensions, including a series of factors such as compression rate, CPU cost and image quality. Also look at the extent of usage of the format, for widely used formats the features and performance benefits are not important. The new format needs to justify its introduction and offer some advantages that the existing format does not offer.

In this regard, Mozilla acknowledges that JPEG-XL offers some potential advantages in terms of functionality and performance.

Still, JPEG-XL’s performance isn’t good enough over its closest competitors, such as AVIF, to justify adding on top of that alone. Likewise, its functional improvements don’t make it stand out from the formats already introduced in the platform.

So Mozilla believes that supporting JPEG-XL has nothing to do with whether it is good or bad for the Web. If JPEG-XL becomes more widely used, we may find it necessary to support the format, but this will be a product decision.

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