1890773 - Provide a pref to control how letter-spacing is applied

Status: RESOLVED FIXED

(Core :: Layout: Text and Fonts, enhancement)

Description

[Jonathan Kew [:jfkthame]]

In https://github.com/w3c/csswg-drafts/issues/10193, I am proposing that the spec for letter-spacing should be changed to call for the spacing to be applied equally on both sides of each character.

While waiting for any conclusions there (which I suspect may take some time), I'd like to implement a pref to allow us to experiment with different behaviors in Gecko, so we can potentially try shipping the new behavior on Nightly at least, and see how it goes in the wild. There will probably be some concerns that changing the behavior may not be web-compatible; by exposing it on Nightly we'd be able to begin to explore whether this is a real issue.

Comment 1

[Jonathan Kew [:jfkthame]]

Attachment: Bug 1890773 - Create a pref to control how letter-spacing is inserted around characters. r=#layout

With the pref set to 0 by default, this does not change any existing behavior.

My intention is that a following patch will set it to 2 in Nightly. This will affect
a bunch of reftests, and so test/expectation adjustments will also be needed.

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/1bb52c5a65eb
Create a pref to control how letter-spacing is inserted around characters. r=layout-reviewers,emilio

Comment 3

[tszentpeteri]

https://hg.mozilla.org/mozilla-central/rev/1bb52c5a65eb