<!DOCTYPE html> <!-- NOTE: This reference case uses the same markup as the testcase, except: (1) This reference case uses modern flexbox CSS instead of -webkit-box. (2) In the 2nd and 4th containers here (where the testcase makes the *2nd* flex item abspos), this reference case simply uses no absolute positioning at all, to produce the correct expected rendering (with the 2nd flex item being positioned after the 1st, rather than being superimposed on top of it). --> <html> <head> <title>Reference: simple positioning of abspos children in -webkit-box</title> <style> .container { border: 1px solid black; width: 200px; } .box { display: flex } .inline-box { display: inline-flex } .abs { position: absolute } .a { border: 3px solid purple } .b { border: 3px solid orange } </style> </head> <body> <!-- Test abspos child in -webkit-box: --> <div class="container box"> <div class="a abs">aa</div> <div class="b">bbbb</div> </div> <div class="container box"> <div class="a">aa</div> <div class="b">bbbb</div> </div> <!-- Test abspos child in -webkit-inline-box: --> <div class="container inline-box"> <div class="a abs">aa</div> <div class="b">bbbb</div> </div> <div class="container inline-box"> <div class="a">aa</div> <div class="b">bbbb</div> </div> </body> </html>