Bug 219735

Summary: Implement ascent-override, descent-override, and line-gap-override
Product: WebKit Reporter: Tobi Reif <tobi>
Component: TextAssignee: Nobody <webkit-unassigned>
Status: NEW    
Severity: Enhancement CC: agafvv, benoit.rouleau, chen.jingan, chrisjshull, chriskirknielsen+wkbugs, fuliang8, gabrien.symons, jesse.bc, karlcow, kizmarh, m.hohengarten, mmaxfield, paul.c.pederson, peter, rasec_1113, rik, taishi.eguchi, tyler, webkit-bug-importer, webkitbugzilla, webkitbugzilla, webkit
Priority: P2 Keywords: BrowserCompat, InRadar
Version: Other   
Hardware: Unspecified   
OS: Unspecified   
Bug Depends on:    
Bug Blocks: 246579    
Attachments:
Description Flags
the general issue none

Tobi Reif
Reported 2020-12-10 02:39:31 PST
It would be very useful if you could implement ascent-override, descent-override, and line-gap-override. More info: https://bugs.chromium.org/p/chromium/issues/detail?id=800693 (especially comments #20, #30 and #31) https://tobireif.com/non_site_stuff/test_case_for_font_position_report_yet_another_font/ https://www.w3.org/TR/css-fonts-4/#font-metrics-override-desc
Attachments
the general issue (12.17 KB, image/png)
2021-02-15 01:52 PST, Tobi Reif 		no flags
Details
View All Add attachment proposed patch, testcase, etc.
Tobi Reif
Comment 1 2020-12-11 02:31:31 PST
Chrome supports it (tested on MacOS vs Windows).
Radar WebKit Bug Importer
Comment 2 2020-12-17 02:40:18 PST
<rdar://problem/72419793>
Tobi Reif
Comment 3 2021-01-08 03:33:03 PST
Here's one reason why it's important to implement this feature: https://tobireif.com/posts/ensuring_the_correct_vertical_position_of_large_text/ (And there's another reason listed in the post below "Another use case".)
Tobi Reif
Comment 4 2021-02-15 01:52:30 PST
Created attachment 420285 [details] the general issue Given that the issue can be as severe as in the attached screenshot, please consider assigning a high priority to implementing this feature.
Tobi Reif
Comment 5 2021-03-23 03:43:55 PDT
Chrome and Edge support the properties, and they are currently getting implemented in Firefox: https://bugzilla.mozilla.org/show_bug.cgi?id=1681691 I hope that they will get implemented in Safari soon.
Tobi Reif
Comment 6 2021-06-25 03:15:28 PDT
Chrome, Edge, and Firefox support it. Safari now is the only major browser which doesn't support this feature. Please implement it soon.
Rick
Comment 7 2022-06-22 04:03:10 PDT
+1 for Safari implementation!
Fu liang
Comment 8 2022-07-17 18:24:28 PDT
+1 for Safari implementation!
Roel Nieskens
Comment 9 2022-09-05 06:43:43 PDT
+1! Any news on when/if this will land?
Jesse Bennett-Chamberlain
Comment 10 2022-09-05 07:59:23 PDT
+1 these properties (along with size-adjust) would be useful for any application that allows users to change their preferred typeface.
Tim Nguyen (:ntim)
Comment 11 2022-10-15 08:41:57 PDT
*** Bug 229726 has been marked as a duplicate of this bug. ***
Cesar
Comment 12 2022-11-30 09:18:29 PST
+1 - Would like to see updates on this
Tyler Sticka
Comment 13 2024-05-15 12:54:34 PDT
+1 Would love to see this happen!
Gabrien Symons
Comment 14 2024-08-20 07:26:33 PDT
+1 to have in Safari!
m.hohengarten
Comment 15 2024-12-03 01:49:15 PST
+1 I'd love to see this 3 years old standard feature on every other browser engine (Blink/Geko supports it since 2021) becoming a standard in all browser engines.
paul.c.pederson
Comment 16 2025-04-21 10:33:39 PDT
Believe it or not the lack of support for this feature in safari is costing us thousands of dollars. @Tim Nguyen (:ntim) is there any way we could get this moved up in the team's queue?
shierote
Comment 17 2026-06-30 23:53:09 PDT
This has been open five years now, with steady interest but no status update. Every other major engine shipped these descriptors in 2021, the spec is stable, and the scope looks modest — so it'd help the community to understand where this stands. @Tim Nguyen (:ntim) Is there a blocker or design concern holding it back, or is it just unstaffed? If it's the latter, is this something an outside contributor could reasonably pick up with some guidance? Happy to help however is useful.
shierote
Comment 18 2026-07-01 18:10:28 PDT
I've implemented all three descriptors (ascent-override, descent-override, line-gap-override) in PR #68431: https://github.com/WebKit/WebKit/pull/68431 Feedback from the Text component owners would be very welcome.
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