<!--quirks mode--> <!-- It's not clear that this is desired behavior, but I'm adding a test for it because bug 243519 *accidentally* regressed it. We're testing here that quirks mode percentage height calculation subtracts the margin, padding, and border of the BODY element when the basis for that percentage height is a specified non-auto height on the HTML element. --> <html style="height: 300px; margin: 1px 0 2px 0; padding: 4px 0 8px 0;"> <head> <title>Testcase, bug 471356 / bug 243519</title> </head> <body style="margin: 16px 0 32px 0; padding: 64px 0 128px 0;"> <!-- basis for percentage is 300px - (16px + 32px + 64px + 128px) == 60px --> <div style="background: blue; height: 50%"> </div> </body> </html>