Bug 164816

Summary: border-bottom style affects table cells to the right when colspan is present.
Product: WebKit Reporter: Jon Kleiser <jon.kleiser>
Component: CSSAssignee: zalan <zalan>
Status: ASSIGNED ---    
Severity: Normal CC: bfulgham, hyatt, simon.fraser, webkit-bug-importer, zalan
Priority: P2 Keywords: InRadar
Version: Safari Technology Preview   
Hardware: Unspecified   
OS: Unspecified   
Attachments:
Description Flags
HTML file that illustrates the problem
none
Test reduction none

Description Jon Kleiser 2016-11-16 00:32:45 PST
Created attachment 294926 [details]
HTML file that illustrates the problem

When one or more cells in a table are given a class that implies a certain border-bottom style, e.g. "border-bottom: 3px solid #f88;", this style sometimes also affects cells to the right of the selected cell(s). This seems to happen only if the affected row is not the final row in the table.
This is demonstrated in the attached HTML file, which may also be seen here: http://folk.uio.no/jkleiser/test/css-bug.html
This file also lists the browsers/OSes where the bug has been seen. I have not tested this on mobile/small devices.
Comment 1 zalan 2016-11-29 15:13:26 PST
Created attachment 295651 [details]
Test reduction
Comment 2 zalan 2016-11-30 16:32:26 PST
This happens because during the collapsed border computation, we ignore the colspan value and pick the before border style for the entire spanning (so the first style wins)
Comment 3 Jon Kleiser 2018-12-12 06:15:44 PST
If my original demo page should be unavailable, a slightly updated page may be found here: https://quickhacks.telegr.am/css-bug.html
Comment 4 Brent Fulgham 2022-07-14 16:55:58 PDT
Safari continues to have this bug in 15.5+
Comment 5 Radar WebKit Bug Importer 2022-07-14 16:56:09 PDT
<rdar://problem/97043314>