Bug 313543

Summary:

Always-on scrollbars are invisible when on root element of nested documents

Product:

WebKit

Reporter:

oss

Component:

Layout and Rendering

Assignee:

alan <zalan>

Status:

RESOLVED FIXED

Severity:

Normal

CC:

bfulgham, simon.fraser, webkit-bug-importer, zalan

Priority:

Keywords:

InRadar

Version:

WebKit Nightly Build

Hardware:

Mac (Apple Silicon)

OS:

macOS 26

Attachments:

Description	Flags
iframe vs normal div scrollbar rendering	none
Test reduction	none
Patch	none
Patch	none
Patch	none
[fast-cq]Patch	none

oss

Reported 2026-04-28 07:29:42 PDT

Created attachment 479353 [details] iframe vs normal div scrollbar rendering When a nested documents scrollingElement (html) is configured as a scroll container w/ "display: flex", its scrollbar thumb is not rendered. See attachment for test/reproduction, which both Gecko and Blink pass.

Attachments
iframe vs normal div scrollbar rendering (6.89 KB, text/html) 2026-04-28 07:29 PDT, oss	no flags	Details
Test reduction (289 bytes, text/html) 2026-04-28 08:00 PDT, alan	no flags	Details
Patch (4.30 KB, patch) 2026-04-28 09:24 PDT, alan	no flags	Details Formatted Diff Diff
Patch (4.32 KB, patch) 2026-04-28 10:48 PDT, alan	no flags	Details Formatted Diff Diff
Patch (4.73 KB, patch) 2026-04-28 17:07 PDT, alan	no flags	Details Formatted Diff Diff
[fast-cq]Patch (6.98 KB, patch) 2026-04-29 05:16 PDT, alan	no flags	Details Formatted Diff Diff
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