- From: Sajid Anwar via GitHub <noreply@w3.org>
- Date: Tue, 30 Dec 2025 17:21:23 +0000
- To: public-css-archive@w3.org
kbhomes has just created a new issue for https://github.com/w3c/csswg-drafts: == [css-inline-3][css-text-3] Clarification on vertical-align shorthand and text boundary shaping == Hey, I'm working on Firefox's implementation of the `vertical-align` shorthand (https://bugzil.la/1830771) and associated `alignment-baseline` and `baseline-shift` properties. I had a question on the expected behavior of the shorthand. The [/css/css-text/boundary-shaping/boundary-shaping-002.html](https://wpt.fyi/results/css/css-text/boundary-shaping/boundary-shaping-002.html) WPT is testing [this line](https://www.w3.org/TR/css-text-3/#:~:text=vertical%2Dalign%20is%20not%20baseline%2E) from css-text-3's "7.3. Shaping Across Element Boundaries": > Text shaping must be broken at inline box boundaries when [...] vertical-align is not baseline. I think this WPT itself was probably already wrong, because it tests the shaping break using `vertical-align: 0`, which [CSS2](https://drafts.csswg.org/css2/#ref-for-value-def-length%E2%91%A1%E2%91%A5) explicitly says is the same as `baseline`. I can fix this test during my implementation. My primary question is about how `baseline-source` fits into this. If the css-text-3 condition of `vertical-align is not baseline` is accurate, then that means any non-initial value for `baseline-source`, `alignment-baseline`, and `baseline-shift` would break shaping. The last two are clear — a different baseline or a non-zero shift _should_ break shaping. But should a non-`auto` value of `baseline-source` do that too? I would think that if changing it to `first` or `last` would have an actual effect on text shaping, then that means it would have been broken anyway. If `baseline-source` _shouldn't_ impact shaping, then does the css-text-3 specification need to change this `vertical-align` condition to specifically `'alignment-baseline' is not 'baseline' and 'baseline-shift' is not '0'`? Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/13277 using your GitHub account -- Sent via github-notify-ml as configured in https://github.com/w3c/github-notify-ml-config
Received on Tuesday, 30 December 2025 17:21:24 UTC