Bug 261752

Summary: When a block quote exactly reaches the bottom of a column, its margin affects the subsequent column [Multicolumn]
Product: WebKit Reporter: Brad Andalman <bya>
Component: Layout and RenderingAssignee: Nobody <webkit-unassigned>
Status: NEW ---    
Severity: Normal CC: bfulgham, simon.fraser, webkit-bug-importer, zalan
Priority: P2 Keywords: InRadar
Version: Safari 16   
Hardware: Mac (Apple Silicon)   
OS: macOS 13   
See Also: https://bugs.webkit.org/show_bug.cgi?id=212505
Attachments:
Description Flags
HTML showing the blockquote margin improperly affecting the next column
none
HTML showing the same behavior as the previous attachment, but in “standard” mode none

Description Brad Andalman 2023-09-19 09:43:17 PDT 
Created attachment 467755 [details]
HTML showing the blockquote margin improperly affecting the next column

I have a <blockquote> that exactly reaches the bottom of a column. Even though it is entirely contained within a single column, the margin-bottom affects the next column.

However, if I decrease the margin-top of the <blockquote> by a single pixel – so that the bottom of the <blockquote> no longer reaches the bottom of the column - then the margin-bottom doesn't affect the subsequent column at all.

This is similar to WebKit bug #212505 (https://bugs.webkit.org/show_bug.cgi?id=212505). It doesn’t seem to be identical, though, because that bug identifies different behavior depending on whether the browser is in quirks mode. For this bug, the behavior is the same regardless of the rendering mode.
Comment 1 Brad Andalman 2023-09-19 09:44:12 PDT 
Created attachment 467756 [details]
HTML showing the same behavior as the previous attachment, but in “standard” mode
Comment 2 Radar WebKit Bug Importer 2023-09-26 09:44:14 PDT 
<rdar://problem/116060548>