Intent to ship: CSS text-autospace property

[Ting-Yu Lin 林庭宇]

As of 2025-10-16, I intend to enable CSS text-autospace property by default in Firefox 146, on all platforms. It has been developed behind the layout.css.text-autospace.enabled preference. Other browsers already ship this feature.

Bug to turn on by default: https://bugzilla.mozilla.org/show_bug.cgi?id=1981086

Standard: https://drafts.csswg.org/css-text-4/#text-autospace-property

This feature was previously discussed in this "Intent to prototype" thread: 
https://groups.google.com/a/mozilla.org/g/dev-platform/c/3Gk5csjxi1s/m/WcRhlTixCAAJ.

Note: this feature has been developed with the initial value normal as in the spec. However, to mitigate the performance regressions and maintain interop with other browsers, we plan to ship with the initial value no-autospace. This differs from the spec's initial value but is allowed by the CSSWG per https://github.com/w3c/csswg-drafts/issues/12386#issuecomment-3028532137

[Ting-Yu Lin 林庭宇]

Given that the CSS text-autospace feature has not changed significantly since Firefox 145 and the release manager approves shipping in beta, it will be available in Firefox 145, too.

Thanks,

Ting-Yu

[一丝]

Thank you for all the hard work you and Firefox have put in, which has greatly benefited the vast CJK user community. This has received overwhelmingly positive feedback from users on x.com.
https://x.com/yisibl/status/1979132340942041270

This is absolutely a major update for Firefox in terms of typography!