195525 2019-03-09 18:04:01 -0800 right:0px on absolutely positioned elements breaks with viewport width=device-width 2019-03-11 17:00:58 -0700 1 1 1 Unclassified WebKit CSS Safari 12 All All REOPENED InRadar P2 Major --- 1 jmoyer webkit-unassigned simon.fraser thorton webkit-bug-importer zalan oldest_to_newest 1514445 0 jmoyer 2019-03-09 18:04:01 -0800 An example page that demonstrates the issue is available at http://jmoyer.nodomain.net/webkitbug.xhtml If an absolutely positioned element, such as the <body/> or its first child, specifies the "right" CSS property with a value of "0px" (and also top, bottom and left), the right side of the element's box moves farther from the right edge of the viewport as the device-width narrows, with significant effects observable on an iPhone 6 in landscape orientation with iOS 12.1.4 and also with Chrome 72.0.3626.119 (64-bit) when in mobile landscape emulation mode. One specific device width tested was 110, where the right side of the element/content isn't even halfway across the viewport. As mentioned in the title, this only occurs with smaller widths of device-width in the viewport <meta/> and pages render correctly in desktop mode, regardless of the viewport width. The upshot of the expected behavior is that content should fill the width (100%) of the viewport and not 66% or 50% in both desktop and mobile rendering modes. Current versions of Firefox and IE were able to render this content as expected. 1514448 1 jmoyer 2019-03-09 18:18:45 -0800 You know, looking into it further, it happens even with statically positioned elements, as the updated example shows. 1514502 2 jmoyer 2019-03-09 21:20:11 -0800 Sorry, this bug is confounding to me. It is real, despite my thinking otherwise for a moment. viewport widths of less than 253 for the included sample, but the problem can be magnified or compounded with other, more complicated stylesheets. 1515107 3 webkit-bug-importer 2019-03-11 17:00:58 -0700 <rdar://problem/48789960>