[Webkit-unassigned] [Bug 262762] New: Implement percentage values for letter-spacing and word-spacing [css-text-4]

[bugzilla-daemon at webkit.org]

https://bugs.webkit.org/show_bug.cgi?id=262762

            Bug ID: 262762
           Summary: Implement percentage values for letter-spacing and
                    word-spacing [css-text-4]
           Product: WebKit
           Version: Safari 17
          Hardware: Unspecified
                OS: Unspecified
            Status: NEW
          Severity: Normal
          Priority: P2
         Component: Text
          Assignee: webkit-unassigned at lists.webkit.org
          Reporter: fantasai.bugs at inkedblade.net
                CC: mmaxfield at apple.com

Background:
  CSS Text Level 4 <https://www.w3.org/TR/css-text-4/> adds support for percentage values of word-spacing and letter-spacing. These inherit as percentages, so that they are always relative to the currently-effective font-size.

Current Status:
  WebKit has support for percentage values of word-spacing (but not calc() values) but calculates them against the width of a space instead of the font-size, and doesn't inherit them properly; and has no support for percentage letter-spacing.

Proposal:
  Re-implement percentage values of word-spacing per spec, add support for percentage values of letter-spacing, and implement support for calc().

Compat Risks:
  Firefox also implements percentage word-spacing in a similar way to WebKit, but Chrome doesn't implement percentage word-spacing, so it's unlikely that Web content depends on it. There could be some lock-in in single-engine environments, but because the current implementation doesn't implement inheritance properly, the benefit of using % over fixed values is not fully realized in the current implementation, so the incentive to use them over 'em' values (which have existed since CSS1) is limited.

-- 
You are receiving this mail because:
You are the assignee for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.webkit.org/pipermail/webkit-unassigned/attachments/20231006/34bc9ac3/attachment.htm>