<?xml version="1.0" encoding="UTF-8" standalone="yes" ?>
<!DOCTYPE bugzilla SYSTEM "https://bugs.webkit.org/page.cgi?id=bugzilla.dtd">

<bugzilla version="5.0.4.1"
          urlbase="https://bugs.webkit.org/"
          
          maintainer="admin@webkit.org"
>

    <bug>
          <bug_id>284123</bug_id>
          
          <creation_ts>2024-12-05 13:14:23 -0800</creation_ts>
          <short_desc>Detect a change in border that affects a positioned object&apos;s height or position</short_desc>
          <delta_ts>2025-01-02 15:31:17 -0800</delta_ts>
          <reporter_accessible>1</reporter_accessible>
          <cclist_accessible>1</cclist_accessible>
          <classification_id>1</classification_id>
          <classification>Unclassified</classification>
          <product>WebKit</product>
          <component>Layout and Rendering</component>
          <version>WebKit Nightly Build</version>
          <rep_platform>Unspecified</rep_platform>
          <op_sys>Unspecified</op_sys>
          <bug_status>RESOLVED</bug_status>
          <resolution>FIXED</resolution>
          
          <see_also>https://bugs.webkit.org/show_bug.cgi?id=284296</see_also>
    
    <see_also>https://github.com/web-platform-tests/wpt/pull/49883</see_also>
          <bug_file_loc></bug_file_loc>
          <status_whiteboard></status_whiteboard>
          <keywords>BrowserCompat, InRadar</keywords>
          <priority>P2</priority>
          <bug_severity>Normal</bug_severity>
          <target_milestone>---</target_milestone>
          
          
          <everconfirmed>1</everconfirmed>
          <reporter name="Ahmad Saleem">ahmad.saleem792</reporter>
          <assigned_to name="alan">zalan</assigned_to>
          <cc>bfulgham</cc>
    
    <cc>karlcow</cc>
    
    <cc>koivisto</cc>
    
    <cc>ntim</cc>
    
    <cc>simon.fraser</cc>
    
    <cc>webkit-bug-importer</cc>
    
    <cc>zalan</cc>
          

      

      

      

          <comment_sort_order>oldest_to_newest</comment_sort_order>  
          <long_desc isprivate="0" >
    <commentid>2079463</commentid>
    <comment_count>0</comment_count>
    <who name="Ahmad Saleem">ahmad.saleem792</who>
    <bug_when>2024-12-05 13:14:23 -0800</bug_when>
    <thetext>Hi Team,

While going through Blink&apos;s commit, I came across another interop bug, where Safari / WebKit is failing.

Test Case: https://jsfiddle.net/7f2j0ox5/1/

^ fails in Safari 18.2 Beta &amp; WebKit ToT, while passes on Chrome Canary 134 and Firefox Nightly 135.

Test Case (2): https://jsfiddle.net/2yj9wpr8/

^ fails in Safari 18.2 Beta &amp; WebKit ToT, while passes on Chrome Canary 134 and Firefox Nightly 135.

Blink Commit: https://chromium.googlesource.com/chromium/src.git/+/4d23825e7f84e0057442cd94f4870547da64c483

Just raising so we can fix it.

Thanks!</thetext>
  </long_desc><long_desc isprivate="0" >
    <commentid>2080085</commentid>
    <comment_count>1</comment_count>
      <attachid>473506</attachid>
    <who name="alan">zalan</who>
    <bug_when>2024-12-08 19:58:34 -0800</bug_when>
    <thetext>Created attachment 473506
[fast-cq]Patch</thetext>
  </long_desc><long_desc isprivate="0" >
    <commentid>2080172</commentid>
    <comment_count>2</comment_count>
    <who name="EWS">ews-feeder</who>
    <bug_when>2024-12-09 05:38:59 -0800</bug_when>
    <thetext>Committed 287543@main (2708384442e4): &lt;https://commits.webkit.org/287543@main&gt;

All reviewed patches have been landed. Closing bug and clearing flags on attachment 473506.</thetext>
  </long_desc><long_desc isprivate="0" >
    <commentid>2080174</commentid>
    <comment_count>3</comment_count>
    <who name="Radar WebKit Bug Importer">webkit-bug-importer</who>
    <bug_when>2024-12-09 05:39:14 -0800</bug_when>
    <thetext>&lt;rdar://problem/141152065&gt;</thetext>
  </long_desc><long_desc isprivate="0" >
    <commentid>2080176</commentid>
    <comment_count>4</comment_count>
    <who name="alan">zalan</who>
    <bug_when>2024-12-09 05:41:16 -0800</bug_when>
    <thetext>This fixes the first case only, I filed bug 284296  for the second one (they are slightly different issues).</thetext>
  </long_desc><long_desc isprivate="0" >
    <commentid>2084577</commentid>
    <comment_count>5</comment_count>
    <who name="Tim Nguyen (:ntim)">ntim</who>
    <bug_when>2025-01-02 15:31:17 -0800</bug_when>
    <thetext>Submitted web-platform-tests pull request: https://github.com/web-platform-tests/wpt/pull/49883</thetext>
  </long_desc>
      
          <attachment
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            <date>2024-12-08 19:58:34 -0800</date>
            <delta_ts>2024-12-09 05:39:00 -0800</delta_ts>
            <desc>[fast-cq]Patch</desc>
            <filename>bug-284123-20241208195833.patch</filename>
            <type>text/plain</type>
            <size>5433</size>
            <attacher name="alan">zalan</attacher>
            
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